Vehicular air conditioning apparatus

ABSTRACT

A vehicular air conditioning apparatus is equipped with a casing having respective air passages therein, and first and second blower units are connected to the casing. Further, the casing is constituted by first and second divided casings. In addition, air is supplied to the interior of the casing from the first and second blower units. Moisture, which is generated when the air is cooled by an evaporator, is guided to forward bottom surfaces of the first and second divided casings and the moisture is discharged to the exterior from first drain ports disposed at terminal end positions of inclined surfaces that decline gradually toward opposite sides of the casing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a vehicular air conditioning apparatusmounted in a vehicle for blowing air into a vehicle compartment that hasbeen adjusted in temperature by a cooling means, for thereby adjustingtemperature of the vehicle compartment.

2. Description of the Related Art

In a vehicular air conditioning apparatus that is mounted in a vehicle,internal and external air is introduced into a casing by a blower, andafter cooled air, which has been cooled by an evaporator that forms acooling means, and heated air, which has been heated by a heater corethat forms a heating means, are mixed together in the casing at apredetermined mixing ratio, the mixed air is blown out from a defrosterblow-out port, a face blow-out port, or a foot blow-out port, wherebyadjustment of temperature and humidity in the vehicle compartment iscarried out.

With this type of vehicular air conditioning apparatus, for example, asdisclosed in Japanese Laid-Open Patent Publication No. 05-178068,Japanese Laid-Open Patent Publication No. 06-040236 and JapaneseLaid-Open Patent Publication No. 06-191257, it is known to provide afirst blower for the purpose of taking in air from the vehiclecompartment into the casing, and a second blower for the purpose oftaking in external air outside of the vehicle compartment into thecasing. In such a vehicular air conditioning apparatus, air that isintroduced from an internal air introduction port by rotation of thefirst blower is heated by a first heat exchanger and then is blown intothe vehicle compartment through a first air passage from the faceblow-out port or the foot blow-out port. In addition, air that isintroduced from an external air introduction port by rotation of thesecond blower is heated by a second heat exchanger and then is blowninto the vehicle compartment through a second air passage from thedefroster blow-out port. More specifically, a switching operation isperformed such that when air is blown out from the face blow-out port orthe foot blow-out port, the first blower is driven and air from theinterior of the vehicle is introduced, whereas when air is blown outfrom the defroster blow-out port, the second blower is rotated andexternal air is introduced.

Further, in another vehicular air conditioning apparatus having firstand second blowers for introducing air, the first blower is arrangedfacing toward an external air inlet port of a duct, and the secondblower is arranged facing toward an interior air inlet port, andtogether therewith, the first blower includes a switching means, whichis capable of switching the air that is introduced to the duct by thefirst blower between interior air and exterior air.

In addition, the air that is introduced to the duct by the first bloweris switched between interior air and exterior air by the switchingmeans, and after the air is mixed with air that is introduced to theduct by the second blower and adjusted in temperature by a heating meansand a cooling means so as to provide a desired temperature, the air isblown into a desired region in the vehicle compartment through a faceblow-out port, a foot blow-out port, or a defroster blow-out port.

In the aforementioned structure, with the vehicular air conditioningapparatus, for example, as disclosed in Japanese Laid-Open PatentPublication No. 2001-180255, when air is cooled by an evaporator thatconstitutes the cooling means thereof, water droplets (hereinafter alsoreferred to as condensate water) are generated on surfaces of theevaporator. When such water droplets are left uncontrolled as is,freezing and build-up of ice occurs, thus reducing the effective area ofthe evaporator, and the heat conversion efficiency of the evaporator isdrastically lowered. Consequently, measures have been taken to dischargesuch water droplets to the exterior.

Recently, in response to demands to increase the vehicle compartmentspace inside of vehicles, it is desirable to reduce the size and scaleof the vehicular air conditioning apparatus, which is mounted in thevehicle.

With respect thereto, with the conventional technique pertaining to theaforementioned Japanese Laid-Open Patent Publication No. 2001-180255, sothat condensate water, which is generated at the evaporator, can bedischarged to the exterior regardless of changes in the posture of thevehicle during running thereof, a bottom surface of the casing isinclined significantly in a downward direction, such that at all timescondensate water is collected toward a water discharge or drainage portprovided on the bottom surface of the casing. Notwithstanding, byadopting such a structure, the dimension in the vertical direction onthe bottom surface portion of the casing becomes large, andaccommodation of the vehicular air conditioning apparatus within thelimited space inside the vehicle is problematic. Stated otherwise,configuring the vehicular air conditioning apparatus in this manner runscontradictory to efforts to reduce the size and scale of the vehicularair conditioning apparatus.

SUMMARY OF THE INVENTION

A general object of the present invention is to provide a vehicular airconditioning apparatus, in which moisture that is generated in a coolingmeans can be discharged reliably and efficiently to the exterior duringtimes of both running and stopping of the vehicle, without regard to theposture of the vehicle, and together therewith, enabling the vehicularair conditioning apparatus to be made small in size and scale.

The present invention is characterized by a vehicular air conditioningapparatus, including a casing having a plurality of passages throughwhich air flows, a blower connected to the casing for supplying the airto the inside of the casing, and cooling means disposed inside thecasing for cooling the air and supplying cooled air, wherein on a bottomsurface of the casing, a plurality of drain ports are provided, whichcommunicate between an interior portion and an exterior portion of thecasing.

More specifically, with the present invention, by providing the pluraldrain ports, which communicate between the interior and the exterior ofthe casing, on the bottom surface of the casing in which the coolingmeans is installed in the interior thereof, moisture that is generatedat the cooling means and which falls therefrom can be quickly andreliably discharged to the exterior through the plural drain ports.Accordingly, by providing a plurality of drain ports, irrespective ofthe posture of the vehicle, such moisture can be reliably andeffectively discharged to the exterior. Further, since a structure isprovided by the plural drain ports for discharging moisture to theexterior, the height dimension of the casing having such drain ports canbe suppressed and the casing can be made smaller in scale, whereby thevehicular air conditioning apparatus can be accommodated within thelimited space of the vehicle.

The above and other objects, features and advantages of the presentinvention will become more apparent from the following description whentaken in conjunction with the accompanying drawings in which preferredembodiments of the present invention are shown by way of illustrativeexample.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external perspective view of a vehicular air conditioningapparatus according to a first embodiment of the present invention;

FIG. 2 is an overall cross sectional view of the vehicular airconditioning apparatus shown in FIG. 1;

FIG. 3 is a cross sectional view taken along line III-III of FIG. 1;

FIG. 4 is an enlarged perspective view showing the vicinity of a bottomportion of a casing in which a pair of drain ports is formed;

FIG. 5 is an enlarged frontal view of the vicinity of a bottom portionof the casing shown in FIG. 3;

FIG. 6 is an enlarged perspective view of the vicinity of a bottomportion of the casing shown in FIG. 4 as seen from an inner side of thecasing;

FIG. 7 is a cross sectional view taken along line VII-VII of FIG. 4;

FIG. 8 is an enlarged side view of a first blower unit in the vehicularair conditioning apparatus shown in FIG. 1;

FIG. 9 is a partial cross sectional view taken along line IX-IX of FIG.2;

FIG. 10 is an external perspective view of a vehicular air conditioningapparatus according to a second embodiment of the present invention;

FIG. 11 is a cross sectional view taken along line XI-XI of FIG. 10;

FIG. 12 is a cross sectional view taken along line XII-XII of FIG. 10;

FIG. 13 is a side view of a first divided casing as seen from aninterior side thereof;

FIG. 14 is a side view of a second divided casing as seen from aninterior side thereof;

FIG. 15 is an enlarged perspective view of (an evaporator holder of) aconnecting duct that fixes an evaporator connected with the firstdivided casing;

FIG. 16 is an enlarged perspective view of the evaporator holder, whichis disposed on an inner wall surface of the second divided casing;

FIG. 17 is a plan view with partial omission showing an evaporator,which is retained on an inner wall surface of the first divided casing;

FIG. 18 is a partial enlarged side view of the evaporator of FIG. 17;

FIG. 19 is an enlarged perspective view of a heater holder disposed onan inside wall surface of the first divided casing;

FIG. 20 is an enlarged perspective view showing the vicinity of a bottomportion of a casing in which a pair of drain ports is formed;

FIG. 21 is an enlarged frontal view of the vicinity of a bottom portionof the casing shown in FIG. 20;

FIG. 22 is an enlarged perspective view of the vicinity of a bottomportion of the casing shown in FIG. 20 as seen from an inner side of thecasing;

FIG. 23 is a cross sectional view taken along line XXIII-XXIII of FIG.20;

FIG. 24 is a plan view of an evaporator;

FIG. 25 is an enlarged side view showing a condition in which theevaporator of FIG. 24 is retained in an evaporator holder, and furtherwherein first and second partitioning members are installed thereon;

FIG. 26 is a perspective view with partial omission of the first andsecond partitioning members shown in FIG. 25;

FIG. 27 is a perspective view with partial omission showing a conditionduring assembly of the first partitioning member and the secondpartitioning member;

FIG. 28 is a perspective view with partial omission showing anevaporator installed state, in which the first partitioning member andthe second partitioning member shown in FIG. 27 are completelyassembled;

FIG. 29 is a cross sectional view with partial omission showing acondition in which a first partitioning member and a second partitioningmember are installed on an evaporator;

FIG. 30 is a front view, partially in cross section, showing a conditionin which a first partitioning member and a second partitioning memberare installed on an evaporator;

FIG. 31 is a plan view of an evaporator according to a modified example,in which a partition plate is installed thereon in place of the firstand second partitioning members of FIG. 30;

FIG. 32 is an enlarged perspective view with partial omission showing acondition in which tubes are retained in the partition plate of FIG. 31;

FIG. 33A is a cross sectional view showing, during a manufacturingprocess for the evaporator, a temporarily assembled state in which tubesare inserted through insertion holes of a partition plate;

FIG. 33B is a cross sectional view showing, during a manufacturingprocess for the evaporator, a state in which, from the condition shownin FIG. 33A, the insertion holes are pressed against sides of the tubesto retain the tubes;

FIG. 34 is a plan view of an evaporator according to a modified examplein which, in place of the first and second partitioning members of FIG.30, louverless portions are provided on fins;

FIG. 35 is an enlarged plan view with partial omission showing thevicinity of the louverless portions of FIG. 34;

FIG. 36 is a cross sectional view taken along line XXXVI-XXXVI of FIG.35;

FIG. 37A and FIG. 37B are enlarged plan views showing a modified exampleof the louverless portion;

FIG. 38 is a plan view of a heater core;

FIG. 39 is a schematic cross sectional view of the heater core shown inFIG. 38;

FIG. 40 is a cross sectional view taken along line XL-XL of FIG. 38;

FIG. 41A is a side view of the heater core of FIG. 38;

FIG. 41B is an enlarged cross sectional view with partial omissionshowing a caulked region of a baffle plate and a housing that make upthe heater core;

FIG. 42 is a schematic cross sectional view of a heater core accordingto a modified example in which a cross sectional cross-shaped baffleplate is utilized;

FIG. 43A is a cross sectional view with partial omission taken alongline XLIIIA-XLIIIA of FIG. 42;

FIG. 43B is a cross sectional view with partial omission taken alongline XLIIIB-XLIIIB of FIG. 42;

FIG. 44 is a partial cutaway perspective view showing a center plate anda dividing panel disposed inside the casing;

FIG. 45 is an exploded perspective view showing a condition in which acover is removed from the first and second divided casings, and adefroster damper and a sub-defroster damper are taken out therefrom;

FIG. 46 is a schematic perspective view of the vehicular airconditioning apparatus showing a condition thereof in which a vent ductand a defroster duct are connected respectively to a first vent blow-outport and a defroster blow-out port;

FIG. 47 is a plan view showing the vehicular air conditioning apparatusof FIG. 46; and

FIG. 48 is an enlarged perspective view showing the vicinity of aconnection duct on which a rotation control device is installed;

FIG. 49 is an enlarged perspective view of the communication duct ofFIG. 44, as seen from the side of an opening portion thereof;

FIG. 50 is an enlarged perspective view showing the vicinity of a firstrear passage and a third rear passage formed in a lower portion of thecasing;

FIG. 51 is an enlarged perspective view of the interior of the casing,showing a modified example of the heater holder shown in FIG. 19;

FIG. 52 is an enlarged perspective view showing a condition in which theheater core is installed in the heater holder of FIG. 51; and

FIG. 53 is a plan view of the heater core of FIG. 52, as viewed fromabove.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment of a vehicular air conditioning apparatusaccording to the present invention shall be presented and explained indetail below with reference to the accompanying drawings. In FIG. 1,reference numeral 200 indicates a vehicular air conditioning apparatusaccording to a first embodiment of the present invention. The vehicularair conditioning apparatus 200, for example, is installed in a vehiclehaving three rows of seats arranged along the direction of travel of thevehicle. In the following descriptions, the first row of seats in thevehicle compartment of the vehicle is designated as front seats, thesecond row of seats is designated as middle seats, and the third row ofseats is designated as rear seats.

Further, the vehicular air conditioning apparatus 200 is installed sothat the righthand side thereof shown in FIG. 2 (in the direction ofarrow A) is oriented toward the front side of the vehicle, whereas thelefthand side (in the direction of arrow B) is oriented toward the rearside of the vehicle. The arrow A direction shall be described as aforward direction, whereas the arrow B direction shall be described as arearward direction.

In the first and second embodiments, as described below, inside thecasing, plural rotating members made up of dampers or the like areprovided, wherein the rotating members are operated by rotational drivesources such as motors or the like. Herein, for purposes ofsimplification, depictions and explanations concerning such rotationaldrive sources have been omitted.

As shown in FIGS. 1 and 2, the vehicular air conditioning apparatus 200according to the first embodiment includes a casing 202 constituted byrespective air passages, a first blower unit 206 connected via aconnection duct 204 to a side portion of the casing 202 for blowing airtoward the front seats of the vehicle, an evaporator (cooling means) 208arranged in the interior of the casing 202 for cooling air, a heatercore 210 for heating the air, a second blower unit 212 connected to alower part of the casing 202 for blowing air to the middle seats andrear seats of the vehicle, and a damper mechanism 214 for switching theflow of air that flows through each of the aforementioned passages.

The casing 202 is constructed from first and second divided casings 216,218 having substantially symmetrical shapes, and a center plate 219disposed between the first divided casing 216 and the second dividedcasing 218. A first intake port 222 connected to the connection duct204, and to which air is supplied from the first blower unit 206, isformed at a lower side portion of the first divided casing 216. Thefirst intake port 222 communicates with a first front passage 224disposed on an upstream side of the evaporator 208.

In this case, the bottom of the casing 202 is inclined gradually,oriented toward end portions in the widthwise direction of the vehicletaking the center thereof as an apex, such that the forward side thereof(in the direction of arrow A) is formed at a lowermost point (see FIGS.2 and 5), with drain ports 226 a, 226 b being disposed in bottom cornerportions thereof. More specifically, the drain ports 226 a, 226 b areformed in tubular shapes and extend in vertically downward directionsrespectively from bottom surfaces 216 a, 218 a of the first and seconddivided casings 216, 218. Further, the drain ports 226 a, 226 b aredisposed in the vicinity of opposite side portions, mutually separatedin the widthwise direction of the casing 202. Additionally, since innerportions of the drain ports 226 a, 226 b communicate with the interiorof the casing 202, moisture that is generated inside the casing 202 andfalls to the bottom surfaces 216 a, 218 a is discharged to the exteriorfrom the drain ports 226 a, 226 b. Moreover, as shown in FIG. 2, thelowermost position of the evaporator 208 faces toward an opening 227disposed in the interior of the casing 202, so that moisture which isgenerated at the evaporator 208 falls toward the bottom surfaces 216 a,218 a from the opening 227 and is discharged to the exterior from thedrain ports 226 a, 226 b.

Furthermore, as stated previously, as shown in FIG. 7, since the bottomsurfaces 216 a, 218 a of the first and second divided casings 216, 218are inclined downward gradually toward opposite side portions of thecasing 202, moisture that falls onto the bottom surfaces 216 a, 218 a isguided suitably to the drain ports 226 a, 226 b and is discharged to theexterior. In this manner, since the drain ports 226 a, 226 b aredisposed at positions where inclined surfaces on the bottom surfaces 216a, 218 a, which gradually decline toward opposite side portions of thecasing 202, terminate, compared to a structure in which the bottomsurfaces 216 a, 218 a are inclined in one direction in the widthwisedirection of the vehicle, the size in the vertical direction of thecasing 202 can be reduced as much as possible. Moreover, the drain ports226 a, 226 b are not limited to being provided in a pair, and three ormore of such drain ports may also be provided. For example, in the casethat the bottom surfaces 216 a, 218 a of the casing 202 are inclined inonly one direction in the widthwise direction of the vehicle, only asingle drain port 226 a may be disposed at a corner portion on thebottom thereof.

Further, even in the case that the casing 202 is mounted on the floor orthe like before the vehicular air conditioning apparatus 200 isinstalled in the vehicle, since the pair of drain ports 226 a, 226 bwhich project from the bottom of the casing 202 are disposed in a pair,the drain ports 226 a, 226 b can be affixed stably as leg portions.Owing thereto, when components such as the first and second blower units206, 212 are assembled onto the casing 202, such assembly can beperformed easily without requiring a specialized jig or the like.

As shown in FIG. 2, the evaporator 208, which is disposed on thedownstream side of the first front passage 224, is disposed to straddlebetween the first divided casing 216 and the second divided casing 218.One end thereof in the forward direction of the vehicle (the directionof arrow A) is inclined downward at a predetermined angle with respectto the other end thereof in the rearward direction (the direction ofarrow B) of the vehicle.

The evaporator 208 includes a first cooling section 228 that faces thefirst front passage 224 and which cools air that is supplied from thefirst front passage 224, and a second cooling section 230 that faces alater-described first rear passage 280 and which cools air that issupplied from the first rear passage 280. The first cooling section 228and the second cooling section 230 are separated by a non-illustratedpartitioning means, so that air flowing from the first front passage 224into the evaporator 208 and air flowing from the first rear passage 280into the evaporator 208 do not mix together mutually inside theevaporator 208.

On the other hand, a second front passage 232 supplied with air that haspassed through the first cooling section 228 is formed on the downstreamside of the evaporator 208. Upwardly of the second front passage 232, athird front passage 234 and a fourth front passage 236 are formed in abranching or bifurcated fashion. Further, a first air mixing damper 238is disposed rotatably in the second front passage 232, so as to facetoward the branching portion of the third front passage 234 and thefourth front passage 236. By rotation of the first air mixing damper238, the blowing condition and blowing rate of the cooled air that haspassed through the evaporator 208 into the third front passage 234 andthe fourth front passage 236 is adjusted. The third front passage 234 isarranged in a forward direction (the direction of arrow A), whereas thefourth front passage 236 is arranged in a rearward direction (thedirection of arrow B), of the casing 202. The heater core 210 isdisposed on a downstream side of the fourth front passage 236.

Upstream of the third front passage 234, a cooling vent damper 240 isdisposed in a downward direction facing the second front passage 232.The cooling vent damper 240 is formed from a butterfly valve, which isrotatable about a central axis, for switching a communication statebetween the second front passage 232 and the third front passage 234.More specifically, because the cooling vent damper 240 is arranged inthe vicinity of the evaporator 208, the cooling vent damper 240 isdisposed such that, under a switching action thereof, chilled air cooledby the evaporator 208 is supplied directly into the third front passage234.

Further, the third front passage 234 extends upwardly, and a first ventblow-out port 242 opens at an upper portion on the downstream sidethereof, where a vent damper 244 is rotatably disposed. The vent damper244 switches a blowing state of air that flows through the third frontpassage 234, when air is blown to the first vent blow-out port 242 andto a later-described sixth front passage 256, and also is capable ofadjusting the blowing rate thereof.

The heater core 210, similar to the evaporator 208, is arranged so as tostraddle between the first divided casing 216 and the second dividedcasing 218, and is disposed such that one end thereof in the forwarddirection of the vehicle (the direction of arrow A) is inclined downwardat a predetermined angle with respect to the other end thereof in therearward direction (the direction of arrow B) of the vehicle. The heatercore 210 includes a first heating section 246 that faces the fourthfront passage 236 and which heats air that is supplied from the fourthfront passage 236, and a second heating section 248 that faces a thirdrear passage 290 (to be described later) and which heats air that issupplied from the third rear passage 290. The first heating section 246and the second heating section 248 are separated by a non-illustratedpartitioning means, so that air flowing from the fourth front passage236 to the heater core 210 and air flowing from the third rear passage290 to the heater core 210 do not mix together mutually inside theheater core 210.

On the downstream side of the heater core 210, a fifth front passage 250is formed. The fifth front passage 250 extends in the forward direction(in the direction of arrow A), and at a location that merges with thedownstream side of the third front passage 234, temperature controldampers 252 a, 252 b are provided, and together therewith, asub-defroster damper 254 is disposed in an upward direction facing theheater core 210. The temperature control dampers 252 a, 252 b, similarto the cooling vent damper 240, are formed from a butterfly valverotatable about a central axis, for switching a communication statebetween the fifth front passage 250 and the third front passage 234 uponrotation thereof, and for deflecting the blowing direction of warm airsupplied from the fifth front passage 250 into the third front passage234.

On the other hand, the sub-defroster damper 254 is disposed so as to becapable of switching a communication state between the fifth frontpassage 250 and the sixth front passage 256 formed thereabove. Byrotating the sub-defroster damper 254 and thereby establishingcommunication between the fifth front passage 250 and the sixth frontpassage 256, that is, by shortening the flow path from the fifth frontpassage 250 to the sixth front passage 256, in a state in which airresistance is reduced, warm air heated by the heater core 210 can besupplied directly to the sixth front passage 256 without flowing throughthe third front passage 234. Owing thereto, in the case that the heatmode for blowing air in the vicinity of the feet of passengers, or thedefroster mode for blowing air in the vicinity of the front window ofthe vehicle, is selected, the blowing rate can be increased to quicklyheat such areas. Stated otherwise, by reducing the influence ofventilation resistance by bending the passage, even without increasingthe rotation of the first blower unit 206, the blowing rate of air inthe heat mode for blowing air in the vicinity of the feet of passengers,or in the defroster mode for blowing air in the vicinity of the frontwindow of the vehicle, can be increased. Furthermore, since the flowpath from the fifth front passage 250 to the sixth front passage 256 isshortened, loss of heat from the warm air heated by the heater core 210is reduced as much as possible when air is blown from the defrosterblow-out port 260 to the front seats, resulting in electrical powersavings during the heat mode and the defroster mode. Moreover, byarranging the sub-defroster damper 254 upwardly of the heater core 210,and arranging the defroster blow-out port 260 further upwardly thereof,the flow of warm air is made substantially linear, such that theventilation resistance when the warm air flows therethrough can bereduced even more.

Further, in a case where the blowing amount of air is fixed, therotation number (rotational frequency, RPM) of the first blower unit 206can be reduced, thereby resulting in electrical power savings during theheat mode and the defroster mode.

Furthermore, during the vent mode, the sub-defroster damper 254 isrotated to establish communication between the fifth front passage 250and the sixth front passage 256, together with rotating the first airmixing damper 238 somewhat in a direction to increase the flow of coolair, so that the blowing rate can be increased without changing thetemperature of the blown out air.

The sixth front passage 256 communicates with the downstream side of thethird front passage 234 through the forwardly disposed opening, andcommunicates with a seventh front passage 258 through the rearwardlydisposed opening. Further, a defroster blow-out port 260 opens upwardlyof the sixth front passage 256, and a defroster damper 262 is disposedrotatably facing the defroster blow-out port 260. The defroster damper262 switches the blowing state of air that is supplied to the sixthfront passage 256 from the third and fifth front passages 234, 250 whenair is blown to the defroster blow-out port 260 and to the seventh frontpassage 258, and further is provided to enable the blowing rate thereofto be adjusted.

More specifically, with the vehicular air conditioning apparatus 200,the first vent blow-out port 242 and the defroster blow-out port 260open upwardly of the casing 202, and are disposed substantiallycentrally in the casing 202, with the first vent blow-out port 242 beingpositioned on the forward side (in the direction of arrow A), and thedefroster blow-out port 260 being positioned rearwardly thereof (in thedirection of arrow B) with respect to the first vent blow-out port 242.

The seventh front passage 258 communicates with a first heat blow-outport (not shown) for blowing air through a heat passage 264 in thevicinity of the feet of passengers riding in the front seats (driver'sseat, passenger seat) of the vehicle compartment.

As shown in FIGS. 1 and 8, the first blower unit 206 comprises anadjustment damper 268 disposed in the inlet of a duct 266 forintroducing exterior air, for adjusting the intake rate of air taken inthrough the duct 266, an intake damper 270 disposed on a downstream sideof the adjustment damper 268 for carrying out switching between interiorand exterior air, and a first blower fan 272 for supplying air taken infrom the duct 266 or the like to the interior of the casing 202. Ablower case 274 in which the first blower fan 272 is accommodated isconnected with the connection duct 204, which in turn is connected tothe first intake port 222, and communicates with the interior of thecasing 202. Rotation of the first blower fan 272 is controlled by a fanmotor (not shown), which is driven by supply of electrical power withrespect to a non-illustrated rotary drive source.

The adjustment damper 268 is disposed to face toward an opening 266 a ofthe duct 266, and is openable and closable via a support shaft 268 a,which is supported on the downstream side of the duct 266. Statedotherwise, the adjustment damper 268 is disposed so as to confront thedirection in which the exterior air is introduced. In addition, throughrotation of the adjustment damper 268 by a predetermined angle upwardlyfrom the closed condition blocking a communication hole 276 (the stateshown by the two-dot-dash line in FIG. 8), which opens on an uppersurface of the blower case 274, the flow rate of intake air to the sideof the blower case 274 through the adjustment damper 268 and thecommunication hole 276 is adjusted. Moreover, an end on the oppositeside of the adjustment damper 268 from the support shaft 268 a isarranged to face toward and confront the air that is drawn in from theduct 266. More specifically, since the flow of air that is drawn in fromthe duct 266 is substantially parallel with the adjustment damper 268,air pressure is not received in a direction perpendicular with respectto the flat surface of the adjustment damper 268, and the adjustmentdamper 268 can be rotated without requiring a large driving force. Inthis case, the direction of extension of the duct 266 and the adjustmentdamper 268 may be arranged substantially in parallel.

For example, the running speed of the vehicle is detected by a vehiclespeed sensor (not shown), and by adjusting the rotation angle (rotationamount) of the adjustment damper 268 based on the running speed, theflow rate of air that is introduced into the casing 202 from theexterior of the vehicle through the duct 266 is controlled to attain afixed rate independently of the vehicle running speed.

More specifically, when the vehicle runs at a high speed, since the rateof air taken in from the duct 266 increases, the opening degree of theadjustment damper 268 is made smaller, and the flow rate of air(external air) supplied to the side of the blower case 274 isrestricted. On the other hand, when the vehicle runs at a low speed,since the rate of air taken in from the duct 266 decreases compared towhen the vehicle runs at a high speed, the opening degree of theadjustment damper 268 is controlled to become larger, so that a greateramount of air (external air) is taken into the interior of the blowercase 274.

As described above, air that is supplied from the first blower unit 206is introduced to the interior of the casing 202 through the connectionduct 204 and the first intake port 222, and under rotating actions ofthe first air mixing damper 238, the vent damper 244, the defrosterdamper 262, the temperature control dampers 252 a, 252 b and thesub-defroster damper 254, which collectively constitute the dampermechanism 214, air is supplied selectively to the defroster blow-outport 260, the first vent blow-out port 242 and the heat passage 264,which are capable of blowing air to the front and middle seats insidethe vehicle through the first through seventh front passages 224, 232,234, 236, 250, 256 and 258.

On the other hand, in a lower portion of the casing 202, as shown inFIG. 2, a second intake port 278 through which air is supplied from thesecond blower unit 212 is formed at a rearward side (in the direction ofarrow B) perpendicular to the first intake port 222. The second intakeport 278 opens at a position on an upstream side of the evaporator 208,and communicates with the first rear passage 280, and further, is formedalongside the first intake port 222 via the first rear passage 280 and afirst dividing wall 281.

The second blower unit 212 includes a second blower fan 282, which takesin air (internal air) from the vehicle compartment and supplies theintake air into the interior of the casing 202. A blower case 284 inwhich the second blower fan 282 is accommodated is connected to thesecond intake port 278 of the casing 202, and communicates with thefirst rear passage 280. In the same manner as the first blower fan 272,rotation of the second blower fan 282 is controlled by a fan motor (notshown), which is driven by supply of electrical power with respect to anon-illustrated rotary drive source.

On a downstream side of the first rear passage 280, a second rearpassage 286 is formed through which air having passed through the secondcooling section 230 of the evaporator 208 is supplied. The second rearpassage 286 is separated from the second front passage 232 by a seconddividing wall 287, wherein the second dividing wall 287 extends to apartition means of the evaporator 208. Owing thereto, on the downstreamside of the evaporator 208 as well, air that passes through the firstrear passage 280 an flows to the second cooling section 230 of theevaporator 208 does not intermix mutually with air that passes throughthe first front passage 224 and flows to the first cooling section 228of the evaporator 208.

Herein, as shown in FIG. 3, the second rear passage 286 and the secondfront passage 232 are separated respectively on sides of the first andsecond divided casings 216, 218 about a center plate 219, which isdisposed in the center of the casing 202, thereby forming a second rearpassage 286 a and a second rear passage 286 b, as well as a second frontpassage 232 a and a second front passage 232 b. Furthermore, as shown inFIG. 9, a pair of communication switching dampers 288 a, 288 b, whichare capable of switching communication states with the second frontpassage 232 a and the second front passage 232 b, are disposed in thesecond rear passage 286 a and the second rear passage 286 b, wherein oneof the communication switching dampers 288 a is rotatably controlledseparately and independently from the other communication switchingdamper 288 b.

In addition, by rotation of the pair of communication switching dampers288 a, 288 b, the second rear passage 286 for blowing air to the middleand rear seats in the vehicle compartment and the second front passage232 for blowing air to the front seats in the vehicle compartment arebrought into mutual communication with each other. Together therewith,by changing, respectively, the rotation amount of one of thecommunication switching dampers 288 a and the rotation amount of theother of the communication switching dampers 288 b, for example, theblowing rate of air blown to the passenger seat side of the front seatsthrough the second front passage 232 a and from the first vent blow-outport 242 a, and the blowing rate of air blown to the driver's seat sideof the front seats through the second front passage 232 b and from thefirst vent blow-out port 242 b, as well as the blowing temperaturesthereof, can be controlled separately from each other.

On a downstream side from the second rear passage 286, a third rearpassage 290 facing the heater core 210 is formed. The third rear passage290 opens onto a side of the heater core 210, and further, opensalongside a fourth rear passage 292 adjacent thereto. In addition, asecond air mixing damper 294, which mixes, at a predetermined mixingratio, cool air and warm air supplied to the third rear passage 290, tothereby form mixed air, is disposed rotatably in the third rear passage290. The second air mixing damper 294 switches the communication statebetween the third rear passage 290 and the upstream or downstream sideof the fourth rear passage 292, which is connected to a downstream sideof the heater core 210. Consequently, by rotating the second air mixingdamper 294, cool air that is cooled by the evaporator 208 and suppliedto the third rear passage 290 and warm air that is heated by the heatercore 210 and which flows through the fourth rear passage 292 are mixedat a predetermined mixing ratio within the fourth rear passage 292, andare blown out therefrom.

In other words, an intermediate location of the fourth rear passage 292functions as a mixing section for mixing warm air and cool air, which isthen blown out to the middle seats and rear seats in the vehiclecompartment.

Further, the fourth rear passage 292, after curving around so as tocircumvent the end portion of the heater core 210, extends downwardlywhile curving to avoid an upper part of the second blower unit 212.Additionally, a downstream side of the fourth rear passage 292communicates with the fifth and sixth rear passages 296, 298 at abranching location of the fifth and sixth rear passages 296, 298, atwhich a rotatable mode switching damper 300 is disposed. By rotating themode switching damper 300, the communication state of the fourth rearpassage 292 with the fifth or sixth rear passages 296, 298 is switched.

The fifth and sixth rear passages 296, 298 extend respectively in therearward direction (the direction of arrow B) of the vehicle. The fifthrear passage 296 communicates with a second vent blow-out port (notshown), which serves to blow air in the vicinity of faces of passengersin the middle seats in the vehicle. On the other hand, the sixth rearpassage 298 communicates with second and third heat blow-out ports (notshown) that serve to blow air in the vicinity of the feet of passengersin the middle and rear seats.

More specifically, air that is supplied from the second blower unit 212is introduced to the interior of the casing 202 through the secondintake port 278. The air then is selectively supplied to a second ventblow-out port, and to the second and third heat blow out ports (notshown), which are capable of blowing air to the middle seats and rearseats in the vehicle, through the first through sixth rear passages 280,286, 290, 292, 296, 298, under rotary actions of the second air mixingdamper 294 and the mode switching damper 300 that constitute the dampermechanism 214.

Moreover, because the aforementioned second to seventh front passages232, 234, 236, 250, 256, 258 and the second rear passage 286 are dividedin half at a substantially central portion of the casing 202 by thecenter plate 219, the second to seventh front passages 232, 234, 236,250, 256, 258 and the second rear passage 286 are disposed respectivelyin the interiors of the first and second divided casings 216, 218.

The vehicular air conditioning apparatus 200 according to the firstembodiment of the present invention is basically constructed asdescribed above. Next, explanations shall be made concerning operationsand effects of the present invention.

First, when operation of the vehicular air conditioning apparatus 200 isstarted, the first blower fan 272 of the first blower unit 206 isrotated upon supply of electricity with respect to a non-illustratedrotary drive source, and air (interior or exterior air) that is taken inthrough the duct 266 or the like is supplied to the first front passage224 of the casing 202 through the connection duct 204. Simultaneously,air (interior air) that is taken in by rotation of the second blower fan282 of the second blower unit 212 upon supply of electricity withrespect to a non-illustrated rotary drive source is supplied to thefirst rear passage 280 from the blower case 274 while passing throughthe second intake port 278. In the following descriptions, the airsupplied to the interior of the casing 202 by the first blower fan 272shall be referred to as “first air,” and the air supplied to theinterior of the casing 202 by the second blower fan 282 shall bereferred to as “second air.”

The first air and the second air supplied to the interior of the casing202 are each cooled by passing respectively through the first and secondcooling sections 228, 230 of the evaporator 208, and flow respectivelyas chilled air to the second front passage 232 and the second rearpassage 286, in which the first air mixing damper 238 and thecommunication switching dampers 288 a, 288 b are disposed. In this case,because the interior of the evaporator 208 is divided into the firstcooling section 228 and the second cooling section 230 by anon-illustrated partitioning means, the first air and the second air donot mix with one another.

Herein, for example, in the case that a vent mode is selected by avehicle occupant for blowing air in the vicinity of the faces ofpassengers, due to the first air mixing damper 238 blockingcommunication between the second front passage 232 and the fourth frontpassage 236, the first air (cooled air) flows from the second frontpassage 232 and through the third front passage 234. In this case, sinceit is unnecessary for warm air that is supplied to the fifth frontpassage 250 to be mixed with respect to the cool air in the third frontpassage 234, the temperature control dampers 252 a, 252 b are rotated soas to be substantially parallel with the third front passage 234,thereby blocking communication between the fifth front passage 250 andthe third front passage 234. In addition, since the vent damper 244 isrotated and communication between the third front passage 234 and thesixth front passage 256 is blocked, the first air (cooled air) thatflows into the third front passage 234 is blown out from the openedfirst vent blow-out port 242 in the vicinity of the faces of passengersin the front seats in the vehicle compartment.

On the other hand, since the communication switching dampers 288 a, 288b block communication between the second front passage 232 and thesecond rear passage 286, the second air (cooled air) flows from thesecond rear passage 286 and to the third rear passage 290. Furthermore,because the second air mixing damper 294 blocks the flow of second airto the heater core 210, the second air (cooled air) flows from the thirdrear passage 290, passing through the fourth rear passage 292, and tothe downstream side. Additionally, under a switching action of the modeswitching damper 300, second air (cooled air) that passes through thefifth rear passage 296 is blown from a second vent blow-out port (notshown) in the vicinity of the faces of passengers in the middle seats inthe vehicle compartment.

Further, for example, in the vent mode, in the case that the vehiclecompartment is to be cooled rapidly, the temperature control dampers 252a, 252 b are rotated to become substantially parallel with the thirdfront passage 234 and to block communication between the fifth frontpassage 250 and the third front passage 234. As a result, cooled air inthe third front passage 234 can be supplied to the first vent blow-outport 242 without being raised in temperature. In addition, because thetemperature control dampers 252 a, 252 b suppress flow passageresistance when cool air flows through the third front passage 234, lowelectrical power consumption of the first blower fan 272 is realized,along with reducing noise. Furthermore, the cooling vent damper 240, byestablishing communication between the second front passage 232 and thethird front passage 234, increases the blowing rate of the first air(cooled air) that flows from the second front passage 232 to the thirdfront passage 234, thereby enabling the vehicle compartment to be cooledrapidly by the first air, which is blown out from the first ventblow-out port 242 and the second vent blow-out port (not shown).

Next, in the case that a bi-level mode is selected for blowing air inthe vicinity of faces and feet of passengers in the vehicle compartment,the first air mixing damper 238 is rotated somewhat more toward the sideof the third front passage 234 than the position thereof during theaforementioned vent mode. Furthermore, the temperature control dampers252 a, 252 b are rotated, whereupon air heated by the heater core 210 issupplied into the third front passage 234 from the fifth front passage250. At this time, the vent damper 244 is positioned at an intermediateposition between the first vent blow-out port 242 and the opening of thesixth front passage 256, while the defroster blow-out port 260 isblocked by the defroster damper 262.

Further, one end of the temperature control dampers 252 a, 252 b, whichare made up of butterfly valves, projects about the support shaft towardthe side of the third front passage 234 (in the direction of arrow A),whereas the lower end side thereof is rotated to project toward the sideof the fifth front passage 250 (in the direction of arrow B), and istilted at a predetermined angle such that the third front passage 234side thereof is inclined upwardly, and the fifth front passage 250 sidethereof is inclined downwardly. Owing thereto, warm air is guided to therearward side in the third front passage 234 along the temperaturecontrol dampers 252 a, 252 b, and the warm air, without being mixed withcooled air, is supplied to the heat passage 264 from the opened sixthfront passage 256 and through the seventh front passage 258, and then isblown out in the vicinity of the feet of passengers riding in the frontseats in the vehicle compartment from a first heat blow-out port (notshown).

On the other hand, because the first vent blow-out port 242 is disposedupwardly of the third front passage 234, a portion of the first air(cooled air) that passes through the evaporator 208 and is supplied fromthe second front passage 232 to the third front passage 234 is blown inthe vicinity of the faces of passengers directly from the first ventblow-out port 242, without being mixed with the heated air.

More specifically, in the bi-level mode, because warm air can be guidedsuitably by the temperature control dampers 252 a, 252 b effectively tothe side of the sixth front passage 256 that communicates with the firstheat blow-out port (not shown), lowering in temperature of the warm airby mixing with cooled air can be suppressed. In addition, rising intemperature of the cooled air by mixing with the heated air can besuppressed as well. As a result, the temperature difference between themixed air that is blown in the vicinity of faces of the passengers fromthe first vent blow-out port 242 and the mixed air that is blown in thevicinity of the feet of passengers from the first heat blow-out port ismade greater, and comfort can be enhanced.

Furthermore, at the same time, the second air mixing damper 294 isrotated in a direction to separate slightly away from the heater core210, and moreover, the mode switching damper 300 is rotated to anintermediate position in the interior of the fourth rear passage 292.Additionally, concerning the second air, warm air that is heated by theheater core 210, and cooled air that is supplied from the third rearpassage 290 to the fourth rear passage 292 through the opening are mixedtogether. The mixed air, after passing through the second vent blow-outport (not shown) from the fifth rear passage 296, is blown out in thevicinity of faces of passengers riding in the middle seats in thevehicle compartment, and together therewith, after passing through thesecond and third heat blow-out ports (not shown) from the sixth rearpassage 298, is blown out in the vicinity of the feet of passengersriding in the middle and rear seats in the vehicle compartment.

Moreover, the sub-defroster damper 254 may be rotated so as to establishcommunication between the fifth front passage 250 and the sixth frontpassage 256. In accordance therewith, first air is added, which passesthrough the heater core 210 and is supplied to the sixth front passage256 via the third front passage 234, and since the first air can besupplied directly into the sixth front passage 256, it is possible toincrease the blowing rate of warm air that is blown from the first heatblow-out port (not shown) in the vicinity of the feet of passengersriding in the front seats of the vehicle compartment. Stated otherwise,warm air that is blown in the vicinity of the feet of passengers can besupplied at a more stable temperature.

Next, in the case that a heat mode is selected for blowing air in thevicinity of the feet of passengers in the vehicle compartment, incomparison to the bi-level mode, the first air mixing damper 238 isrotated further to the side of the third front passage 234. Further, thetemperature control dampers 252 a, 252 b are rotated somewhat to placethe third front passage 234 and the fifth front passage 250 incommunication. Furthermore, the cooling vent damper 240 blockscommunication between the second front passage 232 and the third frontpassage 234, and together therewith, the vent damper 244 and thedefroster damper 262 are rotated respectively to block the first ventblow-out port 242 and the defroster blow-out port 260.

Consequently, heated first air that has passed through the heater core210 is supplied from the fifth front passage 250 to the third frontpassage 234. First air (cooled air) and first air (heated air) are mixedtogether in the third front passage 234, whereupon the mixed air flowsrearwardly through the sixth and seventh front passages 256, 258, issupplied to the heat passage 264, and is blown out from thenon-illustrated first heat blow-out port in the vicinity of the feet ofpassengers riding in the front seats in the vehicle compartment.

Further, similar to the case of the aforementioned bi-level mode, thesub-defroster damper 254 may be rotated to establish communicationbetween the fifth front passage 250 and the sixth front passage 256. Inaccordance therewith, since heated air that has passed through theheater core 210 can be supplied directly into the sixth front passage256, it is possible to increase the blowing rate of the first air thatis blown from the first heat blow-out port (not shown).

On the other hand, the second air mixing damper 294 is rotated in adirection to separate further away from the heater core 210 compared tothe case of the bi-level mode, and further, the mode switching damper300 is positioned to block the fifth rear passage 296. Consequently, thesecond air (mixed air) made up of cooled air and heated air which ismixed in the fourth rear passage 292, after passing through the sixthrear passage 298 from the fourth rear passage 292, is supplied to thesecond and third heat blow-out ports (not shown), where it is blown inthe vicinity of the feet of passengers riding in the middle and rearseats in the vehicle compartment.

Next, an explanation shall be made concerning a heat/defroster mode, inwhich air is blown in the vicinity of the feet of passengers in thevehicle compartment and in the vicinity of the front window foreliminating fog (condensation) from the front window. In the case thatthe heat/defroster mode is selected, the defroster damper 262 is rotatedin a direction to separate from the defroster blow-out port 260, andtogether therewith, the first vent blow-out port 242 is blocked by thevent damper 244 (refer to the solid line in FIG. 2). As a result, aportion of the first air (mixed air), which is mixed in the third frontpassage 234 and the sixth front passage 256, is blown in the vicinity ofthe front window of the vehicle through the defroster blow-out port 260,while the other portion of the first air (mixed air), after passingthrough the sixth and seventh front passages 256, 258, is blown in thevicinity of the feet of passengers in the front seats in the vehiclecompartment from the heat passage 264 and the first heat blow-out port(not shown).

On the other hand, in the heat/defroster mode, in the case that secondair is blown to the middle and rear seats in the vehicle compartment,handling thereof is carried out in the same manner as theabove-described heat mode, and therefore detailed descriptions of thisaspect of the heat/defroster mode are omitted.

Lastly, an explanation shall be made concerning a defroster mode, inwhich blowing of air only in the vicinity of the front window is carriedout for eliminating fog (condensation) from the front window. In thiscase, the first air mixing damper 238 and the cooling vent damper 240block communication between the second front passage 232 and the thirdfront passage 234, and the vent damper 244 is rotated to block the firstvent blow-out port 242. Consequently, heated first air that has passedthrough the heater core 210 is supplied from the fifth front passage250, past the third front passage 234, and to the sixth front passage256. Additionally, since the defroster damper 262 is rotated andcommunication is blocked between the sixth front passage 256 and theseventh front passage 258, the first air (warm air) is supplied from thesixth front passage 256 to the opened defroster blow-out port 260, andis blown in the vicinity of the front window of the vehicle. In thiscase, the defroster mode can be handled by blowing the first air only,which is supplied from the first blower unit 206, without driving thesecond blower unit 212.

Further, as mentioned above, under a switching action of thecommunication switching dampers 288 a, 288 b, by placing the second rearpassage 286 and the second front passage 232 in communication, secondair that is supplied from the second blower unit 212 can also be usedfor carrying out the defroster mode, by supplying the second air to thesecond front passage 232.

Still further, as mentioned above, by rotating the sub-defroster damper254 in a direction to separate away from the sixth front passage 256,and thus directly placing the fifth front passage 250 and the sixthfront passage 256 in communication, heated air that has passed throughthe heater core 210 may be supplied directly into the sixth frontpassage 256 without flowing through the third front passage 234.Consequently, the amount of warm air that is introduced to the sixthfront passage 256 can be increased, and the blowing rate of air that isblown out from the defroster blow-out port 260 can be increasedadvantageously.

In the foregoing manner, according to the first embodiment, because thebottom surfaces 216 a, 218 a of the first and second divided casings216, 218 are configured in an inclined manner, the size in the verticaldirection of the casing 202 can be reduced as much as possible, whilemoisture that falls onto the bottom surfaces 216 a, 218 a is guided tothe drain ports 226 a, 226 b and such moisture can be dischargedefficiently to the exterior of the casing 202. Furthermore, duringassembly thereof, even in the case that the casing 202 is positioned onthe floor or the like, since the pair of first drain ports 226 a, 226 bwhich project from the bottom of the casing 202 are disposed in a pair,the drain ports 226 a, 226 b can be affixed stably as leg portions.

Next, a vehicular air conditioning apparatus 400 according to a secondembodiment is shown in FIGS. 10 to 53. FIG. 11 is a cross sectional viewin a central portion (taken along line XI-XI in FIG. 10) along thewidthwise direction of a vehicular air conditioning apparatus 400,whereas FIG. 12 is a cross sectional view of a region (taken along lineXII-XII in FIG. 10) somewhat deviated to the side of a second dividedcasing 418 from the aforementioned central portion.

As shown in FIGS. 10 to 14, the vehicular air conditioning apparatus 400according to the second embodiment includes a casing 402 constituted byrespective air passages, a first blower unit 406 connected through aconnection duct 404 to a side portion of the casing 402 for blowing airto the front seats in the vehicle, an evaporator (cooling means) 408arranged inside the casing 402 for cooling the air, a heater core 410for heating the air, a second blower unit 412 connected to a lowerportion of the casing 402 for blowing air toward the middle seats andrear seats of the vehicle, and a damper mechanism 414 for switching theflow of air that flows through and inside each of the respectivepassages.

The casing 402 is constituted by first and second divided casings 416,418 having substantially symmetrical shapes, wherein a center plate 420(see FIG. 44) is disposed between the first divided casing 416 and thesecond divided casing 418. The connection duct 404 is connected on alower side portion of the first divided casing 416, and a first intakeport 422 is formed through which air is supplied from the first blowerunit 406. The first intake port 422 communicates with a first frontpassage 424 disposed on an upstream side of the evaporator 408.

As easily understood from FIG. 10, the second blower unit 412 expandsoutwardly and is disposed at a joined region of the substantiallysymmetrical first divided casing 416 and second divided casing 418 thatmake up the casing 402, more specifically, at a center portion of thecasing 402. Further, the second blower unit 412 is positioned inside aconsole of the non-illustrated center vehicle.

As shown in FIGS. 11 to 14, in the first and second divided casings 416,418, an evaporator holder 426 is formed for maintaining the evaporator408, which has a rectangular shape in cross section. The evaporatorholder 426 is provided on a lower part of the casing 402 facing thefirst intake port 422. The evaporator holder 426 includes a firstretaining member 428 that holds one end of the evaporator 408 that isdisposed on the forward side (in the direction of arrow A) of the casing402, and a second retaining member 430 that holds another end of theevaporator 408 that is disposed on the rearward side (in the directionof arrow B) of the casing 402. The first and second retaining members428, 430 are formed with U-shapes in cross section, which open towardone another in mutually facing directions, and extend in the widthwisedirection of the casing 402, from an inner wall surface of the firstdivided casing 416 to an inner wall surface of the second divided casing418.

Further, because the first retaining member 428 confronts the secondretaining member 430 and is disposed downwardly with respect to thesecond retaining member 430, the evaporator 408, which is retained bythe first and second retaining members 428, 430, is disposed such thatone end thereof in the forward direction of the vehicle (the directionof arrow A) is inclined downward at a predetermined angle with respectto the other end thereof.

As shown in FIG. 15, a first rib 432, which projects a predeterminedheight from the inner wall surface at a position between the firstretaining member 428 and the second retaining member 430, is formed onthe inner wall surface of the first divided casing 416, wherein thefirst rib 432 abuts against one side surface of the evaporator 408. Onthe other hand, as shown in FIG. 16, a second rib 434, which projects apredetermined height from the inner wall surface of the second dividedcasing 418 at a position between the first retaining member 428 and thesecond retaining member 430, is formed on the inner wall surfacethereof, confronting the first rib 432, wherein the second rib 434 abutsagainst the other side surface of the evaporator 408.

The first and second ribs 432, 434 are formed respectively withcross-like shapes, such that horizontal ribs 432 a, 434 a thereof, whichextend from the first retaining member 428 to the second retainingmember 430, abut roughly in the center of the evaporator 408 to dividethe evaporator 408 in half in the thickness direction thereof. On theother hand, vertical ribs 432 b, 434 b, which are perpendicular to thehorizontal ribs 432 a, 434 a, abut against a boundary portion in theevaporator 408 of a first cooling section 436 through which air suppliedfrom the first blower unit 406 passes, and a second cooling section 438through which air supplied from the second blower unit 412 passes (referto FIG. 17). Further, compared to the second rib 434, the first rib 432is set to have a greater height from the inner wall surface of the firstdivided casing 416, and the horizontal rib 432 a and vertical rib 432 bare formed perpendicularly with respect to the inner wall surface.

More specifically, by abutment of the horizontal ribs 432 a, 434 a ofthe first and second ribs 432, 434 against side surfaces of theevaporator 408, air is prevented from flowing to the downstream sidebetween inner wall surfaces of the first and second divided casings 416,418 and the evaporator 408. On the other hand, by abutment of thevertical ribs 432 b, 434 b of the first and second ribs 432, 434 againstthe boundary portion of the first cooling section 436 and the secondcooling section 438, air supplied from the first blower unit 406 isprevented from flowing through the side of the second cooling section438 at times when the second blower unit 412 is halted, and conversely,air supplied from the second blower unit 412 is prevented from flowingthrough the side of the first cooling section 436 at times when thefirst blower unit 406 is halted.

Furthermore, on the inner wall surface of the first divided casing 416,a plurality of reinforcement ribs 440 are formed substantially parallelwith the vertical ribs 432 b. The reinforcement ribs 440 are disposedwith respect to upper and lower surface sides of the horizontal rib 432a, and are formed with substantially triangular shapes in cross section,which taper in a direction away from the inner wall surface (see FIGS.15 and 18).

Further, as shown in FIGS. 11 and 12, on the first and second dividedcasings 416, 418, a heater holder 442 is formed for maintaining aheater, which has a rectangular shape in cross section. The heaterholder 442 is provided upwardly of the evaporator holder 426. The heaterholder 442 includes a first retaining member 444 that holds one end ofthe heater core 410 that is disposed on the forward side (in thedirection of arrow A) of the casing 402, and a second retaining member446 that holds another end of the heater core 410 that is disposed onthe rearward side (in the direction of arrow B) of the casing 402. Thefirst retaining member 444 is formed to cover one end portion of theheater core 410, whereas the second retaining member 446 is formed tocover a lower half part only of the other end of the heater core 410.The first and second retaining members 444, 446 extend along thewidthwise direction of the casing 402, from an inner wall surface of thefirst divided casing 416 to an inner wall surface of the second dividedcasing 418.

Further, because the first retaining member 444 confronts the secondretaining member 446 and is disposed downwardly with respect to thesecond retaining member 446, the heater core 410, which is retained bythe first and second retaining members 444, 446, is disposed such thatone end thereof in the forward direction of the vehicle (the directionof arrow A) is inclined downward at a predetermined angle with respectto the other end thereof.

Furthermore, as shown in FIG. 19, a rib 448, which projects apredetermined height from the inner wall surface at a position betweenthe first retaining member 444 and the second retaining member 446, isformed on the inner wall surface of the first divided casing 416, suchthat the rib 448 abuts against one side surface of the heater core 410.The rib 448 is formed with a cross-like shape, such that a horizontalrib 448 a thereof, which extends from the first retaining member 444 tothe second retaining member 446, abuts roughly in the center of theheater core 410 to divide the heater core 410 in half in the thicknessdirection thereof. On the other hand, a vertical rib 448 b, which isperpendicular to the horizontal rib 448 a, abuts against a boundaryportion in the heater core 410 of a first heating section 450 throughwhich air supplied from the first blower unit 406 passes, and a secondheating section 452 through which air supplied from the second blowerunit 412 passes (refer to FIG. 13). Further, in the second dividedcasing 418, a region thereof opens in a direction facing toward theheater core 410.

More specifically, by abutment of the horizontal rib 448 a of the rib448 against a side surface of the heater core 410, air is prevented fromflowing to the downstream side between the inner wall surface of thefirst divided casing 416 and the heater core 410. At the same time, byabutment of the vertical rib 448 b against the boundary portion of thefirst heating section 450 and the second heating section 452, airsupplied from the first blower unit 406 is prevented from flowingthrough the side of the second heating section 452 at times when thesecond blower unit 412 is halted, and conversely, air supplied from thesecond blower unit 412 is prevented from flowing through the side of thefirst heating section 450 at times when the first blower unit 406 ishalted.

Moreover, reinforcement ribs similar to the reinforcement ribs 440provided on the evaporator holder 426 may also be provided on the heaterholder 442. More specifically, by providing such reinforcement ribssubstantially parallel with the vertical rib 448 b, strength of thehorizontal rib 448 a can be increased and the heater core 410 can besupported more firmly, while leakage of air between the heater core 410and the first and second divided casings 416, 418 can be prevented.

On the other hand, as shown in FIGS. 11 and 20, the bottom portion ofthe casing 402 is formed such that the front side thereof (in thedirection of arrow A) is lowest, with a pair of first drain ports 454 a,454 b being disposed at this location. The first drain ports 454 a, 454b are formed in tubular shapes and extend in vertically downwarddirections from forward bottom surfaces 416 a, 418 a on a forward side(the direction of arrow A) from a first guide panel 456 in the first andsecond divided casings 416, 418. Further, the first drain ports 454 a,454 b are disposed in the vicinity of opposite side portions, mutuallyseparated in the widthwise direction of the casing 402, and communicatefrom the interior of the casing 402 to the exterior thereof.

Further, as shown in FIGS. 11 to 14, on the bottom portion of the casing402, the first guide panel 456 is formed, which faces toward the firstfront passage 424 on a forward side (in the direction of arrow A)adjacent to the first drain ports 454 a, 454 b. The first guide panel456 is arranged in an upstanding manner along the extending direction ofthe first front passage 424. An upper end part thereof extends to thevicinity of the lower surface of the evaporator 408, and is bent in adirection (the direction of arrow B) separating from the evaporatorholder 426 that retains the evaporator 408.

Owing thereto, in the evaporator 408, for example, although watercondensation is generated when air passing through the interior of theevaporator 408 is cooled, because one end side thereof is disposed to beinclined downwardly at a predetermined angle, moisture that is generatedinside the evaporator 408 can be moved to one end side, i.e., the frontside of the vehicle (in the direction of arrow A), along the lowersurface of the evaporator 408.

Further, when the moisture moves along the lower surface of theevaporator 408, it comes into contact with the upper end of the firstguide panel 456 and is guided downwardly along the first guide panel456, and falls onto rearward bottom surfaces 416 b, 418 b (see FIG. 22)that form a bottom surface between the first guide panel 456 and a firstdividing wall 572 in the first and second divided casings 416, 418. Inaddition, the fallen moisture is guided to the forward bottom surfaces416 a, 418 a of the first and second divided casings 416, 418 through ahole 456 a disposed at a bottom part of the first guide panel 456 (seeFIG. 22). Since the first drain ports 454 a, 454 b are disposed atpositions where inclined surfaces of the forward bottom surfaces 416 a,418 a, which gradually decline toward opposite side portions of thecasing 402, terminate (see FIG. 23), moisture that is guided toward theforward bottom surfaces 416 a, 418 a is directed suitably to the firstdrain ports 454 a, 454 b and is discharged to the exterior.

In this case, although the rearward bottom surfaces 416 b, 418 b areinclined downwardly toward the hole 456 a such that fallen moisture isguided suitably to the hole 456 a, the inclination of the rearwardbottom surfaces 416 b, 418 b is not strictly limited to this form.

Further, in this manner, since the first drain ports 454 a, 454 b aredisposed at positions where inclined surfaces on the forward bottomsurfaces 416 a, 418 a, which gradually decline toward opposite sideportions of the casing 402, terminate, compared to a structure in whichthe forward bottom surfaces 416 a, 418 a are inclined in one directionin the widthwise direction of the vehicle, the size in the verticaldirection of the casing 402 can be reduced as much as possible. Also, inFIG. 19, although only one hole 456 a is provided, the invention is notnecessarily limited to this feature, and two or more of such holes mayalso be provided.

Owing thereto, accumulation and retention of moisture discharged fromthe evaporator 408 within the first front passage 424, thus becoming acause of foul odors, and further, leakage of moisture into the interiorof the vehicle compartment, are prevented.

Moreover, the first drain ports 454 a, 454 b are not limited to beingprovided in a pair, and three or more drain ports may also be provided.

Further, even in the case that the casing 402 is mounted on the floor orthe like before the vehicular air conditioning apparatus 400 isinstalled in the vehicle, since the pair of first drain ports 454 a, 454b which project from the bottom of the casing 402 are disposed in apair, the first drain ports 454 a, 454 b can be mounted stably as legportions. Owing thereto, when components such as the first and secondblower units 406, 412 are assembled onto the casing 402, such assemblycan be performed easily without requiring a specialized jig or the like.

As shown in FIG. 24, in the evaporator 408, for example, tubes 458 a,458 b are formed from thin plates of aluminum or the like, and fins 460,which are folded in a serpentine-like undulating shape, are disposedrespectively between the stacked tubes 458 a, 458 b. On the fins 460, aplurality of louvers 462 are formed, which are cut out so as to beinclined at predetermined angles with respect to the planar surface ofthe fins 460. By causing a coolant medium to flow through the interiorof the tubes 458 a, 458 b, air that passes through the louvers 462 andflows between the fins 460 is cooled by the coolant medium and issupplied to the downstream side as chilled air. At the evaporator 408,the paired tubes 458 a, 458 b are arrayed in parallel and arranged intwo layers in the thickness direction of the evaporator 408.

Further, the evaporator 408 includes the first cooling section 436,which cools air supplied from the first blower unit 406, and the secondcooling section 438, which cools air supplied from the second blowerunit 412. Additionally, the first cooling section 436 is arranged in theforward direction (the direction of arrow A) of the casing 402, whereasthe second cooling section 438 is arranged in the rearward direction(the direction of arrow B) of the casing 402.

At the boundary region between the first cooling section 436 and thesecond cooling section 438, as shown in FIG. 25, a pair of first andsecond partitioning members 464, 466 are installed for blockingcommunication of air between the first cooling section 436 and thesecond cooling section 438. As shown in FIGS. 26 to 28, the first andsecond partitioning members 464, 466 are formed from a resin material,for example, and are equipped with straightly formed base portions 468a, 468 b, and a plurality of sealing portions 470 a, 470 b, whichproject at a predetermined length from the lower surface of the baseportions 468 a, 468 b. Also, projections 472 a, 472 b are formedthereon, which project in a direction perpendicular to the lengthwisedirection, centrally along the lengthwise direction of the sealingportions 470 a, 470 b. The sealing portions 470 a, 470 b are formed withthe same length, and are disposed so as to be separated mutually atequal intervals along the base portions 468 a, 468 b. Further, theprojections 472 a, 472 b project in the same directions with respect tothe sealing portions 470 a, 470 b.

Additionally, as shown in FIG. 25, the first partitioning member 464 ismounted on a lower surface side of the evaporator 408 on the upstreamside thereof, such that the sealing portions 470 a thereof are insertedrespectively between the stacked tubes 458 a, 458 b in the evaporator408, and the base portion 468 a abuts against the lower surface. On theother hand, the second partitioning member 466 is mounted on an uppersurface side of the evaporator 408 on the downstream side thereof, suchthat the sealing portions 470 b thereof are inserted on an opposite sidefrom the first partitioning member 464 between the tubes 458 a, 458 b,and the base portion 468 b abuts against the upper surface.

At this time, as shown in FIG. 29, the sealing portions 470 a of thefirst partitioning member 464 and the sealing portions 470 b of thesecond partitioning member 466 are offset from each other along thedirection of extension (the direction of arrow C) of the base portions468 a, 468 b, and further, overlap in the direction of extension of thetubes 458 a, 458 b. Owing to the two sealing portions 470 a, 470 b,which are mutually overlapped in this manner, intervals between adjacenttubes 458 a, 458 b in the same layer are sealed respectively. Next,projections 472 a of the first partitioning member 464 and theprojections 472 b of the second partitioning member 466 are insertedbetween the adjacent tubes 458 a and the tubes 458 b, while the firstpartitioning member 464 and the second partitioning member 466 are slidrespectively along the direction of extension (the direction of arrow C)of the base portions 468 a, 468 b. Consequently, the projections 472 aof the first partitioning member 464 and the projections 472 b of thesecond partitioning member 466 overlap in the direction of extension ofthe tubes 458 a, 458 b, and gaps occurring between the tubes 458 adisposed on the upper surface side and the tubes 458 b disposed on thelower surface side are sealed (see FIG. 30).

Consequently, since the flow of air between the tubes 458 a, 458 b,which are disposed in two layers, is blocked by the first and secondpartitioning members 464, 466 installed between the first coolingsection 436 and the second cooling section 438, flow of air between thefirst cooling section 436 and the second cooling section 438 isprevented (see FIG. 29).

Moreover, in a condition of being installed on the evaporator 408, thebase portions 468 a, 468 b of the first and second partitioning members464, 466 are retained respectively in base holders 578, 588, which areformed in the casing 402 (see FIG. 25).

Further, the means for blocking communication of air between the firstcooling section 436 and the second cooling section 438 in the evaporator408 is not limited to the aforementioned first and second partitioningmembers 464, 466. For example, as shown in FIG. 31, in place of theaforementioned first and second partitioning members 464, 466, aplate-shaped partition plate 474 may also be disposed at the boundaryregion between the first cooling section 436 and the second coolingsection 438.

The partition plate 474, as shown in FIGS. 31 and 32, includes aplurality of insertion holes 476 therein through which the tubes 458 a,458 b are inserted. Pressing members 478, which are inclined atpredetermined angles from the partition plate 474 about centers of theinsertion holes 476, are formed in openings of the insertion holes 476.The pressing members 478 are substantially chevron shaped in crosssection about the center of the insertion holes 476, and are tiltablewith a certain resiliency in a radial direction of the insertion holesabout a fulcrum point defined by an adjoining region with the partitionplate 474.

In addition, for example, a cut line or seam is disposed in fins 460 aforming a boundary between the first cooling section 436 and the secondcooling section 438. After the partition plate 474 is inserted betweenthe fins 460 a, the tubes 458 a, 458 b are inserted respectively throughthe insertion holes 476 of the partition plate 474 (see FIG. 33A). Then,in such a provisionally assembled state, as shown in FIG. 33B, apressing force P is applied respectively from the right and left in adirection to approach mutually toward the plural tubes 458 a, 458 b, andwhile heat is applied thereto, welding (e.g., using solder) is carriedout, whereby the tubes 458 a, 458 b, the fins 460 a, and the partitionplate 474 are mutually bonded together to manufacture the evaporator 408(see FIG. 31).

At this time, the pressing members 478 of the partition plate 474contact the side surfaces of the tubes 458 a, 458 b due to the pressingforce P, and further, because the tubes 458 a, 458 b are retained by theresilient force thereof, a state in which the partition plate 474 andthe tubes 458 a, 458 b are mutually positioned can be realized. Byperforming welding in such a positioned state, for example, generationof thermal shrinkage after welding and the occurrence of gaps betweenthe partition plate 474 and the tubes 458 a, 458 b is prevented.

Furthermore, in place of the above-discussed first and secondpartitioning members 464, 466 or the partition plate 474, for example,as shown in FIGS. 34 and 35, louverless portions 480, without thelouvers 462 being provided thereon, may also be formed in fins 460 b, ata boundary region located between the first cooling section 436 and thesecond cooling section 438. As a result thereof, as shown in FIG. 36, byproviding the louverless portions 480 at an intermediate location of thefins 460 b that have the louvers 462 thereon, flow of air through thelouvers 462 is interrupted, and flowing of air between the first coolingsection 436 and the second cooling section 438 can be prevented.

Further, the aforementioned louverless portions 480 are not limited to acase of being provided as a unitary body with the fins 460 b having thelouvers 462. For example, as shown in FIG. 37A, cutouts may be providedin the fins 460 b having the louvers 462 thereon, wherein U-shapedlouverless portions 480 a are then inserted through the cutouts andjoined therein. Similarly, as shown in FIG. 37B, louverless portions 480b having elliptical shapes in cross section may be inserted therein andjoined, so as to prevent air from flowing between the first coolingsection 436 and the second cooling section 438.

On the other hand, as shown in FIG. 11, on a downstream side of theevaporator 408, a second front passage 482 is formed, through which airhaving passed through the first cooling section 436 is supplied.Upwardly of the second front passage 482, a third front passage 484 anda fourth front passage 486 are formed in a branching or bifurcatedmanner. Further, a first air mixing damper 488 is rotatably disposed soas to face toward the branching portion of the third front passage 484and the fourth front passage 486.

By rotation of the first air mixing damper 488, the blowing conditionand blowing rate of the cooled air that has passed through theevaporator 408 into the third front passage 484 and the fourth frontpassage 486 is adjusted. The third front passage 484 is arranged in theforward direction (the direction of arrow A), whereas the fourth frontpassage 486 is arranged in the rearward direction (the direction ofarrow B), of the casing 402. The heater core 410 is disposed on adownstream side of the fourth front passage 486.

Upstream of the third front passage 484, a cooling vent damper 490 isdisposed in a downward direction facing the second front passage 482,for switching a communication state between the second front passage 482and the third front passage 484. More specifically, because the coolingvent damper 490 is arranged in the vicinity of the evaporator 408, thecooling vent damper 490 is disposed such that, under a switching actionthereof, chilled air cooled by the evaporator 408 is supplied directlyinto the third front passage 484.

Further, the third front passage 484 extends upwardly, and a first ventblow-out port 492 opens at an upper portion on the downstream sidethereof, where a vent damper 494 is rotatably disposed. The vent damper494 switches a blowing state of air that flows through the third frontpassage 484, when the air is blown to the first vent blow-out port 492and a later described sixth front passage 520, and also is capable ofadjusting the blowing rate thereof.

The heater core 410 is arranged to straddle between the first dividedcasing 416 and the second divided casing 418, and is disposed such thatone end thereof in the forward direction of the vehicle (the directionof arrow A) is inclined downward at a predetermined angle with respectto the other end thereof in the rearward direction (the direction ofarrow B) of the vehicle. The heater core 410 includes the first heatingsection 450 that heats air supplied from the first blower unit 406, andthe second heating section 452 that heats air supplied from the secondblower unit 412, wherein the first heating section 450 is arranged onthe forward side of the casing 402.

As shown in FIG. 38, in the heater core 410, tubes 496 a, 496 b areformed from thin plates of aluminum or the like, and fins (not shown),which are folded in a serpentine-like undulating shape, are disposedrespectively between the stacked tubes 496 a, 496 b. On the fins, aplurality of louvers are formed, which are cut out so as to be inclinedat predetermined angles with respect to planar surfaces of the fins. Bycausing heated water to flow through the interior of the tubes 496 a,496 b, air that passes through the louvers and flows between the fins isheated by the heated water and is supplied to the downstream side asheated air. At the heater core 410, the tubes 496 a, 496 b are arrayedin parallel and arranged in two layers in the thickness direction of theheater core 410.

On both ends of the tubes 496 a, 496 b, respective hollow tank portions503 a, 503 b are connected, which retain the heated water that flowsinside the tubes 496 a, 496 b. In addition, as shown in FIGS. 38 and 39,on one of the tank portions 503 a on a side surface of the heater core410, a supply conduit 498 through which heated water is supplied fromthe exterior, and a discharge conduit 500 through which heated waterhaving circulated through the interior of the heater core 410 isdischarged, are connected respectively. The discharge conduit 500 isarranged in the vicinity of a corner portion in a rear upward directionof the casing 402, whereas the supply conduit 498 is arranged inparallel adjacent to the discharge conduit 500.

On the other hand, in the interior of the tank portion 503 a, a baffleplate 502 is disposed, which is substantially L-shaped in cross section.The baffle plate 502 extends at a predetermined width in an extendingdirection (the direction of arrow E) of the supply conduit 498 and thedischarge conduit 500, and the baffle plate 502 is arranged between oneof the tubes 496 a and the other of the tubes 496 b. Additionally, asshown in FIG. 40, the pair of tubes 496 a, 496 b are separated insidethe tank portion 503 a by the baffle plate 502.

The baffle plate 502, as shown in FIG. 39, is made up from a planarportion 504 arranged centrally in the thickness direction of the heatercore 410 and a bent portion 506, which is bent at a right angle at oneend of the planar portion 504. The bent portion 506 is disposed betweenthe discharge conduit 500 and the supply conduit 498.

Further, on the baffle plate 502, a plurality of caulking projections507 (see FIG. 41A) are disposed respectively on both ends thereof alongthe longitudinal direction (the direction of arrow E) of the heater core410. After such caulking projections 507 have been inserted throughholes formed in a side surface of the tank portion 503 a to projectoutwardly therefrom, the projecting regions thereof are pressed andcrushed by a non-illustrated jig or the like (see FIG. 41B). Moreover,the caulking projections 507 are formed with rectangular shapes in crosssection and are disposed while being mutually separated at predetermineddistances on side surfaces of the planar portion 504 and the bentportion 506. Together therewith, holes facing the planar portion 504 aredisposed centrally in the thickness direction on the tank portion 503 a,and holes facing the bent portion 506 are disposed at positions betweenthe supply conduit 498 and the discharge conduit 500 (see FIG. 41A).

As a result thereof, the baffle plate 502 is affixed securely withrespect to the tank portion 503 a disposed on the end of the heater core410.

In addition, heated water supplied from the supply conduit 498 issupplied, via the one tank portion 503 a, to one of the tubes 496 a,which is disposed on the upper side. Then, after the heated water hasflowed through the tube 496 a to the other end side of the heater core410, the heated water reverses direction inside the tank portion 503 bdisposed at the other end of the heater core 410, passes through theother tube 496 b disposed on the lower side, and flows along the lowersurface side of the baffle plate 502 back to the one end side of theheater core 410 whereupon, the heated water is discharged from thedischarge conduit 500.

At this time, since the discharge conduit 500 is connected at an uppercorner portion 411 (in the rearward direction) of the heater core 410,which is inclined at a predetermined angle, even in the case thatentrapped or retained air is generated inside the heater core 410, theair can be reliably discharged to the exterior through the dischargeconduit 500, which is connected at the upper corner portion 411 wheresuch retained air is generated. Stated otherwise, the discharge conduit500 is connected at an uppermost position in the heater core 410, theheater core 410 being disposed at a predetermined angle of inclinationinside the casing 402.

Further, the baffle plate 502, which is disposed inside the heater core410, is not limited to having an L-shape in cross section, as describedabove. For example, as shown in FIG. 42, a baffle plate 508 having across-like shape in cross section in a heater core 410 a may also beused.

As shown in FIG. 42, the baffle plate 508 includes a planar portion 510and a vertical portion 512 that intersects at a right angle with respectto the planar portion 510. The planar portion 510 is arranged centrallyin the thickness direction of the heater core 410 a, and the verticalportion 512 is arranged between the discharge conduit 500 and the supplyconduit 498.

Further, as shown in FIG. 43A, on the vertical portion 512, on the lowersurface side of the heater core 410 a, a through hole 512 a opensthrough which the circulated heated water can flow. Furthermore, asshown in FIG. 43B, on the planar portion 510 facing the dischargeconduit 500, another through hole 510 a opens through which the heatedwater can flow. Additionally, in the heater core 410 a employing thebaffle plate 508, heated water supplied from the supply conduit 498 issupplied to the interior of one of the tank portions 503 a, and flowsalong an upper surface side of the baffle plate 508 and is supplied toone of the tubes (not shown). Additionally, after reversing in directionat the tank portion 503 b disposed on the other end side of the heatercore 410 a, the heated water flows along the lower surface side of thebaffle plate 508, and after flowing to the through hole 510 a of theplanar portion 510 from the through hole 512 a of the vertical portion512, the heated water is discharged from the discharge conduit 500 viathe tank portion 503 a.

At this time as well, since the discharge conduit 500 is connected at anupper corner portion 411 a (in the rearward direction) of the heatercore 410 a, which is inclined at a predetermined angle, even in the casethat entrapped or retained air is generated inside the heater core 410a, the air can be reliably discharged to the exterior through thedischarge conduit 500, which is connected at the upper corner portion411 a where such retained air is generated.

As shown in FIG. 12, on the downstream side of the heater core 410, afifth front passage 514 is formed. The fifth front passage 514 extendsin the forward direction (in the direction of arrow A), and at alocation that merges with the third front passage 484, a temperaturecontrol damper 516 is provided, and together therewith, sub-defrosterdampers 518 a, 518 b are disposed in an upward direction facing theheater core 410. Under a rotating action of the temperature controldamper 516, a communication state between the fifth front passage 514and the third front passage 484 is switched, for deflecting the blowingdirection of warm air supplied from the fifth front passage 514 into thethird front passage 484.

On the other hand, the sub-defroster dampers 518 a, 518 b are disposedso as to be capable of switching a communication state between the fifthfront passage 514 and the sixth front passage 520 formed thereabove. Byrotating the sub-defroster dampers 518 a, 518 b and thereby establishingcommunication between the fifth front passage 514 and the sixth frontpassage 520, i.e., by shortening the fluid passage from the fifth frontpassage 514 to the sixth front passage 520, warm air heated by theheater core 410 can be supplied directly to the sixth front passage 520without flowing through the third front passage 484, in a state in whichventilation resistance of the fluid passage is reduced.

Owing thereto, in the case that a heat mode for blowing air in thevicinity of the feet of passengers, or a defroster mode for blowing airin the vicinity of the front window of the vehicle, is selected, theblowing rate can be increased to quickly heat such areas.

Stated otherwise, even without increasing the rotation of the firstblower unit 406, the blowing rate of air during the heat mode and thedefroster mode can be increased.

The sixth front passage 520 communicates with the downstream side of thethird front passage 484 through the forwardly disposed opening, andcommunicates with a later-described seventh front passage 522 throughthe rearwardly disposed opening. A defroster blow-out port 524 opensupwardly of the sixth front passage 520, with a pair of defrosterdampers 526 a, 526 b being disposed rotatably therein facing thedefroster blow-out port 524.

The defroster dampers 526 a, 526 b are provided to switch the blowingstate when the air supplied to the sixth front passage 520 is blown outfrom the defroster blow-out port 524, and further are capable ofadjusting the blowing rate thereof.

Further, at a downstream side of the sixth front passage 520, a pair ofheat dampers 528 made up from a butterfly valve are rotatably disposed(see FIG. 11). By rotating the heat dampers 528, the blowing state ofair is switched, when air supplied from the sixth front passage 520 isblown out through later-described seventh and eighth front passages 522,540 or through the defroster blow-out port 524, and further, the blowingrate of such air can be adjusted.

Further, as shown in FIG. 44, the sixth front passage 520 is dividedinto two sections by the center plate 420, which is disposed centrallyin the casing 402 in the widthwise direction thereof. Also, the sixthfront passage 520 is further divided respectively by a pair of dividingpanels 530 a, 530 b, which are disposed roughly centrally in thewidthwise direction of the first and second divided casings 416, 418. Inaddition, in the sixth front passage 520, between the center plate 420and the dividing panels 530 a, 530 b, the pair of heat dampers 528 aredisposed, such that air that flows between the center plate 420 and thedividing panels 530 a, 530 b is directed outwardly to a first heatpassage 538 (discussed later) under rotating actions of the heat dampers528.

On the other hand, the defroster dampers 526 a, 526 b are disposedrespectively between the dividing panels 530 a, 530 b and inner wallsurfaces of the first and second divided casings 416, 418, so that airthat flows between the dividing panels 530 a, 530 b and inner wallsurfaces of the first and second divided casings 416, 418 is directedoutwardly, respectively, from side portions 534 of the defrosterblow-out port 524 under rotating actions of the defroster dampers 526 a,526 b.

More specifically, the sixth front passage 520 is divided into foursections inside the casing 402 by the pair of dividing panels 530 a, 530b and the center plate 420, such that the blowing state and blowing rateof air that is blown from the defroster blow-out port 524 is switched bythe defroster dampers 526 a, 526 b.

As shown in FIG. 45, by respectively removing covers 536 a, 536 b, whichare disposed alongside the defroster dampers 526 a, 526 b and thesub-defroster dampers 518 a, 518 b in the first and second dividedcasings 416, 418, maintenance thereon, such as exchanging and adjustmentof rotation angles, etc., can easily be carried out on the defrosterdampers 526 a, 526 b and the sub-defroster dampers 518 a, 518 b.

The seventh front passage 522 communicates with a first heat blow-outport (not shown) through the first heat passage 538 for the purpose ofblowing air in the vicinity of the feet of passengers in the front seatsin the vehicle compartment. The eighth front passage 540 extendsdownwardly in a curving manner and communicates with a second heatblow-out port (not shown) upwardly of the second blower unit 412 througha second heat passage (not shown) for the purpose of blowing air in thevicinity of the feet of passengers in the middle seats in the vehiclecompartment.

In the casing 402, the first vent blow-out port 492 and the defrosterblow-out port 524 open upwardly of the casing 402, and further, thefirst vent blow-out port 492 is arranged on a forward side (in thedirection of arrow A), whereas the defroster blow-out port 524 isarranged rearwardly, substantially centrally in the casing 402 withrespect to the first vent blow-out port 492 (see FIG. 12).

As shown in FIGS. 46 and 47, a vent duct 544, which extends whilecurving toward the rearward side of the vehicle (in the direction ofarrow B), is connected to the first vent blow-out port 492 for supplyingmixed air to the vicinity of faces of passengers in the front seats ofthe vehicle compartment from the first vent blow-out port 492. A pair ofcenter vent ducts 546 that make up the vent duct 544 are connected to acenter portion of the first vent blow-out port 492 and blow air towardthe center of the front seats, whereas another pair of side vent ducts548, which are connected to both ends of the first vent blow-out port492, extend in lateral directions of the front seats, and blow airtoward the driver's seat and passenger seat sides thereof.

On the other hand, a defroster duct 550, which extends while curvingtoward the forward side of the vehicle (in the direction of arrow A), isconnected to the defroster blow-out port 524 for supplying mixed air tothe vicinity of the front window in the vehicle compartment from thedefroster blow-out port 524. The defroster duct 550 is constituted bycenter defroster ducts 552, which are branched in a forked manner so asto avoid the center vent ducts 546 that extend upwardly of the defrosterblow-out port 524, and extend toward an unillustrated front window, andside defroster ducts 554 which extend perpendicularly to the centerdefroster ducts 552 in lateral directions together with the side ventducts 548. The center defroster ducts 552 extend toward the forward side(in the direction of arrow A) straddling upwardly over the side ventducts 548.

More specifically, the vent duct 544 connects to the first vent blow-outport 492 disposed on the forward side and extends rearwardly (in thedirection of arrow B) toward the vehicle compartment, whereas thedefroster duct 550 connects to the defroster blow-out port 524 disposedon the rearward side and extends in a forward direction (in thedirection of arrow A) on the front window side while crossing over thevent duct 544.

In this manner, by arranging the first vent blow-out port 492 on theforward side of the casing 402, the third front passage 484 thatcommunicates between the downstream side of the evaporator 408 and thefirst vent blow-out port 492 can be laid out in a straight line fashion,while the defroster blow-out port 524 can be disposed upwardly of theheater core 410.

In this case, the center defroster ducts 552 and the side defrosterducts 554 that constitute the defroster duct 550 extend respectivelyfrom the side portions 534 of the defroster blow-out port 524, such thatthe center vent ducts 546 are oriented and can extend rearwardly (in thedirection of arrow B) from the first vent blow-out port 492, which isdisposed forwardly (in the direction of arrow A) of the defrosterblow-out port 524.

The first blower unit 406 includes an intake damper (not shown) in whichan external air intake port 556 connected to a duct (not shown) for thepurpose of introducing external air and an internal air intake port 558for introducing internal air are arranged in an opening thereof, andwhich carries out switching between the external and internal air, and afirst blower fan 560 that supplies air that is taken in to the interiorof the casing 402. A blower case 562 in which the first blower fan 560is accommodated communicates with the interior of the casing 402 throughthe connection duct 404 connected to the first intake port 422. Rotationof the first blower fan 560 is controlled by a fan motor (not shown),which is driven under the control of a later-described rotation controldevice 564 a.

Further, the connection duct 404 has a shape in which the crosssectional area of a passage thereof is greater than a later-mentionedfirst rear passage 570, which forms the connection passage of the secondblower unit 412. Further, as shown in FIGS. 48 and 49, the connectionduct 404 is formed in a tubular shape having a substantially rectangularshape in cross section, wherein two rotation control devices 564 a, 564b are installed on wall portions thereof. The rotation control devices564 a, 564 b are capable of controlling the air-blowing rate to theinside of the casing 402, by controlling respectively the rotationnumber (RPM) of the first blower fan 560 and a second blower fan 574.The rotation control devices 564 a, 564 b are arranged inside theconnection duct 404 at positions where the fluid passage cross sectionalarea thereof is maximal. In addition, the rotation control devices 564a, 564 b are arranged perpendicularly to each other, and a plurality ofheat dissipating fins 566 a, 566 b are mounted so as to project into thepassage of the connection duct 404. Specifically, by placing the heatdissipating fins 566 a, 566 b in contact with air that flows inside theconnection duct 404, since heat generated by the rotation controldevices 564 a, 564 b can suitably be dissipated via the heat dissipatingfins 566 a, 566 b, the rotation control devices 564 a, 564 b can becooled effectively.

More specifically, air supplied from the first blower unit 406 isintroduced to the interior of the casing 402 through the connection duct404 and the first intake port 422. By rotation of the first air mixingdamper 488, the vent damper 494, the defroster dampers 526 a, 526 b, theheat dampers 528, and the sub-defroster dampers 518 a, 518 b that makeup the damper mechanism 414, air is selectively supplied to thedefroster blow-out port 524, the first vent blow-out port 492, the firstheat passage 538, and the second heat passage (not shown), which arecapable of blowing air to the front seats and middle seats in thevehicle, through the first through seventh front passages 424, 482, 484,486, 514, 520 and 522.

On the other hand, in a lower portion of the casing 402, as shown inFIGS. 11 and 12, a second intake port 568 through which air is suppliedfrom the second blower unit 412 is formed at a rearward sideperpendicular to the first intake port 422. The second intake port 568opens at a position on an upstream side of the evaporator 408, andcommunicates with the first rear passage 570, and further, is formedalongside the first intake port 422 via the first rear passage 570 andthe first dividing wall 572.

The second blower unit 412 includes the second blower fan 574, whichsupplies air that has been taken in to the interior of the casing 402. Ablower case 576 in which the second blower fan 574 is accommodated isconnected to the second intake port 568 of the casing 402 andcommunicates with the first rear passage 570. In the same manner as thefirst blower fan 560, rotation of the second blower fan 574 iscontrolled by a fan motor (not shown) driven under the control of therotation control device 564 b.

On a downstream side of the first rear passage 570, the evaporator 408is disposed such that the second cooling section 438 thereof faces thefirst rear passage 570. The first dividing wall 572, which is formedbetween the first rear passage 570 and the first front passage 424,extends to the first and second partitioning members 464, 466 that areinstalled on the evaporator 408. The first partitioning member 464 isretained in the base holder 578, which is disposed at the end of thefirst dividing wall 572.

More specifically, since the first dividing wall 572 extends to thefirst and second partitioning members 464, 466 that are installed on theevaporator 408, air that flows to the evaporator 408 through the firstrear passage 570 is prevented from mixing with air that flows to theevaporator 408 through the first front passage 424.

Further, a second guide panel 580 for guiding moisture ejected from theevaporator 408 to the bottom of the casing 402 is formed in the firstrear passage 570 while being separated a predetermined distance from thefirst dividing wall 572. An upper end of the second guide panel 580extends to the vicinity of the base holder 578 disposed on the firstdividing wall 572, and is bent rearwardly so as to be separated apredetermined distance from the base holder 578 (see FIG. 16).

In addition, in the event that moisture generated by the second coolingsection 438 of the evaporator 408 flows to the forward side (in thedirection of arrow A) along the lower surface of the evaporator 408 andis retained in the first partitioning member 464 and the base holder578, or when such moisture comes into contact with the upper end of thesecond guide panel 580, the moisture is guided and flows downwardlyalong the second guide panel 580. The moisture is then discharged fromthe casing 402 through a second drain port 582 disposed between thefirst dividing wall 572 and the second guide panel 580.

Owing thereto, condensed water that is generated in the evaporator 408is prevented from accumulating and freezing in the evaporator 408.

On a downstream side of the evaporator 408, a second rear passage 584 isformed, to which air having passed through the second cooling section438 of the evaporator 408 is supplied. The second rear passage 584 isseparated from the second front passage 482 by a second dividing wall586, wherein the second partitioning member 466 is retained in the baseholder 588 disposed at the end of the second dividing wall 586.Specifically, because the second dividing wall 586 extends to the secondpartitioning member 466 installed on the evaporator 408, on thedownstream side of the evaporator 408 as well, air that flows to thesecond cooling section 438 of the evaporator 408 through the first rearpassage 570 does not intermix with air that passes through the firstfront passage 424 and flows to the first cooling section 436 of theevaporator 408.

In the second rear passage 584, a second air mixing damper 590 isdisposed rotatably therein facing the heater core 410 for mixing cooledair and heated air at a predetermined mixing ratio to thereby producemixed air. The second air mixing damper 590 switches the communicationstate between the second rear passage 584 and an upstream or downstreamside of a third rear passage 592, which is connected to a downstreamside of the heater core 410. Consequently, by rotating the second airmixing damper 590, cool air that is cooled by the evaporator 408 andsupplied to the second rear passage 584 and warm air that is heated bythe heater core 410 and which flows through the third rear passage 592are mixed at a predetermined mixing ratio within the third rear passage592 and blown out therefrom.

Stated otherwise, the third rear passage 592 functions as a mixingsection for mixing warm air and cool air, which is then blown out to themiddle seats and rear seats in the vehicle.

Further, as shown in FIG. 11, the third rear passage 592, after bendingto circumvent the other end of the heater core 410, extends downwardly,and midway therein, an opening is formed that communicates with thesecond rear passage 584. On a downstream side extending further downwardfrom the opening, as shown in FIG. 50, the third rear passage 592branches in a forked manner, branching in widthwise directions of thecasing 402 about the first rear passage 570, and after extending so asto avoid the first rear passage 570 on both sides thereof, the thirdrear passage 592 merges again downward of the first rear passage 570.Stated otherwise, the third rear passage 592 is formed so as to crossover the first rear passage 570.

As shown in FIGS. 11 and 12, on a downstream side of the third rearpassage 592, fourth and fifth rear passages 594, 596 communicatetherewith. A rotatable mode switching damper 598 is disposed at abranching location thereof, which serves to switch the blowing state ofair to the fourth and fifth rear passages 594, 596, which branchrespectively from the third rear passage 592, and also to adjust theblowing rate of air thereto.

The fourth and fifth rear passages 594, 596 extend toward a rearwarddirection of the vehicle. The fourth rear passage 594 communicates witha second vent blow-out port (not shown) for blowing air in the vicinityof faces of passengers in the middle seats in the vehicle compartment.The fifth rear passage 596 communicates with second and third heatblow-out ports (not shown) for blowing air in the vicinity of the feetof passengers in the middle and rear seats.

Specifically, air supplied from the second blower unit 412 is directedinto the casing 402 through the second intake port 568, and isselectively supplied to the second vent blow-out port, and the secondand third heat blow out ports, which are arranged to face the middleseats and rear seats in the vehicle, through the first through fifthrear passages 570, 584, 592, 594, 596.

Moreover, because the aforementioned second to seventh front passages482, 484, 486, 514, 520, 522 are divided in half at a substantiallycentral portion of the casing 402 by the center plate 420, the second toseventh front passages 482, 484, 486, 514, 520, 522 are disposedrespectively inside of the first and second divided casings 416, 418.

An explanation shall now be made with reference to FIGS. 51 to 53concerning a modified example of a heater holder 442 a for retaining theheater core 410 inside the casing 402.

In the heater holder 442 a, a pair of ribs 600 a, 600 b (sealingmembers) are formed, which project toward and abut against the sidesurfaces of the heater core 410 at center portions of first and secondretaining members 444 a, 446 a. The paired ribs 600 a, 600 b aredisposed at a substantially central portion of the casing 402 coplanarwith the center plate 420 provided in the casing 402, and extend roughlyin a vertical direction. Stated otherwise, the pair of ribs 600 a, 600 bis disposed substantially parallel with the blowing direction of airthat flows through the interior of the casing 402.

On the other hand, at a substantially center portion of the heater core410, a partitioning means 602 is disposed along a straight line so as tounite one of the ribs 600 a and the other of the ribs 600 b, andfurther, is disposed at a position substantially coplanar with thecenter plate 420 provided inside the casing 402 when the heater core 410is mounted in the heater holder 442 a. The heater core 410 is separatedinto a first heating section 450 a, which is arranged on the side of thefirst divided casing 416 centrally about the center plate 420 by thepartitioning means 602, and a second heating section 452 a, which isarranged on the side of the second divided casing 418, and prevents flowof air through the interior of the heater core 410 between the firstheating section 450 a and the second heating section 452 a thereof (seeFIG. 53).

Stated otherwise, the partitioning means 602 disposed on the heater core410 and the pair of ribs 600 a, 600 b provided on the heater holder 442a are arranged perpendicularly to the first and second partitioningmembers 464, 466 provided on the evaporator 408, and the vertical ribs432 b, 434 b in the evaporator holder 426.

In addition, air that is supplied from the first blower fan 560 andflows through the fourth front passage 486 to the heater core 410, andair that is supplied from the second blower fan 574 and flows throughthe second rear passage 584 to the heater core 410, are dividedrespectively by the partitioning means 602 into the first and secondheating sections 450 a, 452 a, whereby such air, which is separated inthe first divided casing 416 and the second divided casing 418, isheated and flows downstream. Furthermore, because the ribs 600 a, 600 bof the heater holder 442 a are arranged along a straight line with thepartitioning means 602, air that flows through the first divided casing416 side and air that flows through the second divided casing 418 sidecentrally about the center plate 420 in the casing 402 are preventedfrom intermixing.

More specifically, after air, which has been cooled by the evaporator408, flows through the fourth front passage 486 and the second rearpassage 584, passes through the first and second heating sections 450 a,452 a of the heater core 410 and is heated thereby, by supplying the airto the fifth front passage 514 and the third rear passage 592, which areseparated bilaterally within the casing 402, for example, mixed airwhich is adjusted in temperature separately and independently is blownout respectively from the vent blow-out port on the driver's seat sideand the vent blow-out port on the passenger seat side inside the vehiclecompartment.

The vehicular air conditioning apparatus 400 according to the secondembodiment of the present invention is basically constructed asdescribed above. Next, operations and effects of the invention shall beexplained.

First, when operation of the vehicular air conditioning apparatus 400 isstarted, the first blower fan 560 of the first blower unit 406 isrotated under the control of the rotation control device 564 a, and air(interior or exterior air) that is taken in through a duct or the likeis supplied to the first front passage 424 of the casing 402 through theconnection duct 404. Simultaneously, air (interior air) that is taken inby rotation of the second blower fan 574 of the second blower unit 412under the control of the rotation control device 564 b is supplied tothe first rear passage 570 from the blower case 576 while passingthrough the second intake port 568. In the following descriptions, airsupplied to the interior of the casing 402 by the first blower fan 560shall be referred to as “first air,” and air supplied to the interior ofthe casing 402 by the second blower fan 574 shall be referred to as“second air.”

The first air and the second air supplied to the interior of the casing402 are each cooled by passing respectively through the first and secondcooling sections 436, 438 of the evaporator 408, and flow respectivelyas chilled air to the second front passage 482 and the second rearpassage 584, in which the first and second air mixing dampers 488, 590are disposed. In this case, because the interior of the evaporator 408is divided into the first cooling section 436 and the second coolingsection 438 by a non-illustrated partitioning means, the first air andthe second air do not mix with one another.

Herein, for example, in the case that a vent mode is selected by avehicle occupant through a controller (not shown) in the vehiclecompartment for blowing air in the vicinity of the faces of passengers,by blocking communication between the second front passage 482 and thefourth front passage 486 by means of the first air mixing damper 488,the first air (cooled air) flows from the second front passage 482 tothe third front passage 484. In this case, the temperature controldamper 516 blocks communication between the fifth front passage 514 andthe third front passage 484. Additionally, concerning the first air(cooled air) that flows to the third front passage 484, since the ventdamper 494 is rotated into a position that blocks communication betweenthe third front passage 484 and the sixth front passage 520, the firstair is blown from the open first vent blow-out port 492, through thevent duct 544, and in the vicinity of the faces of passengers riding inthe front seats in the vehicle compartment.

On the other hand, concerning the second air (cooled air), since flow tothe second heating section 452 of the heater core 410 is interrupted bythe second air mixing damper 590, the second air flows downstream fromthe second rear passage 584 through the third rear passage 592.Additionally, the second air (cooled air) is blown in the vicinity ofthe faces of passengers riding in the middle seats in the vehiclecompartment from the second vent blow-out port (not shown) through thefourth rear passage 594 under a switching operation of the modeswitching damper 598.

Further, for example, in the vent mode, in the case that the interior ofthe vehicle compartment is quickly cooled, the cooling vent damper 490enables communication between the second front passage 482 and the thirdfront passage 484. As a result, since the blowing rate of the first air(cooled air) that flows to the third front passage 484 from the secondfront passage 482 increases, the vehicle compartment can be cooledquickly by the first air, which is blown from the first vent blow-outport 492 through the vent duct 544.

In this case, since it is unnecessary to mix warm air supplied to thefifth front passage 514 with the cool air of the third front passage484, the temperature control damper 516 is rotated to becomesubstantially parallel with the third front passage 484 and to blockcommunication between the fifth front passage 514 and the third frontpassage 484. As a result, cooled air in the third front passage 484 canbe supplied to the first vent blow-out port 492 without being raised intemperature. In addition, because the temperature control damper 516suppresses flow passage resistance when cool air flows through the thirdfront passage 484, low electrical power consumption of the first blowerfan 560 is realized, along with reducing noise.

Next, for example, in the case that the bi-level mode is selected by thecontroller (not shown) inside the vehicle compartment for blowing air inthe vicinity of faces and feet of the passengers, the first air mixingdamper 488 is rotated to an intermediate position between the thirdfront passage 484 and the fourth front passage 486, so that the firstair is caused to flow respectively to both the third front passage 484and the fourth front passage 486. Furthermore, the temperature controldamper 516 is rotated, whereupon air heated by the first heating section450 of the heater core 410 is supplied into the third front passage 484from the fifth front passage 514. At this time, the vent damper 494 ispositioned at an intermediate position between the first vent blow-outport 492 and the opening of the sixth front passage 520, and togethertherewith, the defroster blow-out port 524 is blocked by the defrosterdampers 526 a, 526 b, whereupon the communication opening from the fifthfront passage 514 to the sixth front passage 520 is blocked by thesub-defroster dampers 518 a, 518 b and communication therebetween isinterrupted.

Herein, the first air (cooled air) flows from the second front passage482 to the third front passage 484. In this case, the temperaturecontrol damper 516 is oriented in a direction so as to be separated fromthe communication opening between the fifth front passage 514 and thethird front passage 484, while the end portion thereof is rotated toface the upstream side of the third front passage 484. Specifically, thefirst air (cooled air) is heated by the first heating section 450 of theheater core 410, and by mixing only at a small amount with the first air(heated air) that flows to the third front passage 484 through the fifthfront passage 514, air is blown directly from the first vent blow-outport 492, through the vent duct 544, and in the vicinity of the faces ofpassengers riding in the front seats in the vehicle compartment.

In this case, since the temperature control damper 516 is rotated sothat the end portion thereof confronts the upstream side of the thirdfront passage 484 and projects into the third front passage 484, warmair is guided to the upstream side of the third front passage 484 alongthe temperature control damper 516, and further mixing thereof withcooled air can be promoted. Further, concerning the heat dampers 528 inthe form of a butterfly valve, one end side thereof is rotated about thesupport axis to project toward the side of the sixth front passage 520(in the direction of arrow A), while the other end side thereof isrotated to project toward the side of the seventh front passage (in thedirection of arrow B).

Consequently, warm air that is mixed with cool air in the third frontpassage 484 flows from the sixth front passage 520, through the seventhfront passage 522, and to the first heat passage 538, and is blown inthe vicinity of the feet of passengers who ride in the front seat in thevehicle compartment, and together therewith, is blown in the vicinity ofthe feet of passengers who ride in the middle seats in the vehiclecompartment, from the eighth front passage 540 and through the secondheat passage (not shown).

Further, the sub-defroster dampers 518 a, 518 b may be rotated so as toestablish communication between the fifth front passage 514 and thesixth front passage 520. As a result, air that passes through the firstheating section 450 of the heater core 410 is added to the first air,which has been supplied to the sixth front passage 520 via the thirdfront passage 484, whereupon warm first air can be supplied directlywith respect to the sixth front passage 520. Owing thereto, it ispossible to increase the blowing rate of warm air that is blown in thevicinity of the feet of passengers in the front seat in the vehiclecompartment from the first heat blow-out port (not shown). Statedotherwise, warm air blown in the vicinity of the feet of passengers canbe supplied at a more stable temperature.

On the other hand, concerning the second air (cooled air), the secondair mixing damper 590 is rotated to an intermediate position whereby thesecond air flows to the second heating section 452 of the heater core410, and together therewith, flows to the third rear passage 592connected to the second rear passage 584. Specifically, the second air,after having been cooled by the second cooling section 438 of theevaporator 408, is divided in flow by the second air mixing damper 590,such that one portion is guided to the third rear passage 592 as cooledair, whereas the other portion thereof, after being heated by the secondheating section 452 of the heater core 410, is blown into the third rearpassage 592. As a result, the second air is adjusted to a suitabletemperature in the third rear passage 592.

The angle of rotation of the second air mixing damper 590 can be freelychanged in accordance with the temperature desired by passengers in thevehicle compartment, or stated otherwise, the second air mixing damper590 can be rotated in coordination with an input from the controller inthe vehicle compartment. Concerning the second air, which flowsdownstream through the third rear passage 592, the flow rate ratiothereof to the fourth rear passage 594 and the fifth rear passage 596 isadjusted by rotating the mode switching damper 598 to a predeterminedposition so that the second air flows therethrough. As a result, thesecond air is blown from the second vent blow-out port and a second heatblow-out port (not shown) in the vicinity of the faces of passengers inthe middle seats inside the vehicle compartment, or alternatively, isblown from the second heat blow-out port and the third heat blow-outport (not shown) toward the feet of passengers in the middle seats andrear seats inside the vehicle compartment. Herein, the predeterminedposition of the mode switching damper 598 is defined in accordance withthe set temperature and mode, which are input by a passenger from thecontroller inside the vehicle compartment. The set temperature and/ormode, apart from being input from the front seats, may also be inputfrom the middle seats or the rear seats.

Next, in the case that the heat mode for performing blowing of air inthe vicinity of the feet of passengers in the vehicle compartment isselected by the controller (not shown) in the vehicle compartment,compared to the case of the bi-level mode, the first air mixing damper488 is rotated more to the side of the third front passage 484. Further,the temperature control damper 516 is rotated somewhat to establishcommunication between the third front passage 484 and the fifth frontpassage 514. Furthermore, the cooling vent damper 490 blockscommunication between the second front passage 482 and the third frontpassage 484, and the vent damper 494 and the defroster dampers 526 a,526 b are rotated respectively so that the first vent blow-out port 492and the defroster blow-out port 524 are closed.

At this time, similar to the aforementioned bi-level mode, concerningthe heat dampers 528 which are formed from a butterfly valve, one endside is rotated about the support axis to project into the sixth frontpassage 520 (in the direction of arrow A), whereas the other end side isrotated to project into the seventh front passage 522 (in the directionof arrow B).

As a result thereof, the heated first air that has passed through thefirst heating section 450 of the heater core 410 is supplied to thethird front passage 484 from the fifth front passage 514. In the thirdfront passage 484, the first air (cooled air), which has flowed in fromthe second front passage 482, is mixed with the first air (heated air),whereupon the mixed air passes through the sixth front passage 520 andthe seventh front passage 522 and flows rearwardly. In addition, afterbeing supplied to the first heat passage 538, air is blown from anon-illustrated first heat blow-out port in the vicinity of the feet ofpassengers riding in the front seat in the vehicle compartment, and fromthe eighth front passage 540 air is blown out via a non-illustratedsecond heat passage in the vicinity of the feet of passengers in themiddle seats in the vehicle compartment.

In this case, since the end of the temperature control damper 516 isrotated toward the upstream side of the third front passage 484projecting into the third front passage 484, the warm air is guideddownstream of the third front passage 484 along the temperature controldamper 516, and mixing thereof with the cooled air can be promoted.

Further, the sub-defroster dampers 518 a, 518 b may be rotated toestablish communication between the fifth front passage 514 and thesixth front passage 520. In accordance therewith, air passes through thefirst heating section 450 of the heater core 410 and is added to thefirst air supplied to the sixth front passage 520 via the third frontpassage 484, and such heated first air can be supplied directly withrespect to the sixth front passage 520. Owing thereto, the air blowingrate of warm air, which is blown in the vicinity of the feet ofpassengers in the front seat in the vehicle compartment from the firstheat blow-out port, can be increased. Stated otherwise, warm air blownin the vicinity of the feet of passengers can be supplied at a morestable temperature.

On the other hand, compared to the case of the bi-level mode, the secondair mixing damper 590 is rotated somewhat to separate away from theheater core 410, whereupon second air, which has passed through thesecond heating section 452 of the heater core 410, flows downstreamthrough the third rear passage 592. By rotating the mode switchingdamper 598 to a position blocking the fourth rear passage 594, thesecond air passes through the fifth rear passage 596 and is blown in thevicinity of the feet of passengers in the middle and rear seats in thevehicle compartment from the second heat blow-out port and the thirdheat blow-out port (not shown).

Next, an explanation shall be made concerning a heat-defroster mode, inwhich by means of the controller (not shown) in the vehicle compartment,air is blown both in the vicinity of the feet of passengers in thevehicle compartment, and in the vicinity of the front window foreliminating fog (condensation) on the front window.

In the case that the heat-defroster mode is selected, the defrosterdampers 526 a, 526 b in the form of a butterfly valve are rotated aboutthe support axis so as to separate from the defroster blow-out port 524,together with blocking the first vent blow-out port 492 by the ventdamper 494 (refer to the broken line in FIG. 12). As a result thereof, aportion of the first air (mixed air) that is mixed in the third frontpassage 484 passes through the defroster blow-out port 524 and is blownin the vicinity of the front window in the vehicle. Further, anotherportion of the first air (mixed air) passes through the sixth andseventh front passages 520, 522, and is blown in the vicinity of thefeet of passengers in the front seats in the vehicle compartment throughthe first heat passage 538, as well as being blown in the vicinity ofthe feet of passengers in the middle seats in the vehicle compartmentfrom the eighth front passage 540 through a non-illustrated second heatpassage.

Further, in the heat-defroster mode, in the case that second air isblown toward the middle seats and rear seats of the vehicle compartment,since this mode is the same as the heat mode discussed above, detailedexplanations thereof shall be omitted.

Lastly, the defroster mode for blowing air only in the vicinity of thefront widow for eliminating fog (condensation) from the front window inthe vehicle shall be described. In this case, the first air-mixingdamper 488 and the cooling vent damper 490 block communicationrespectively between the second front passage 482 and the third frontpassage 484. At the same time, the vent damper 494 blocks the first ventblow-out port 492 and blocks communication between the vent duct 544 andthe third front passage 484, while the temperature control damper 516establishes communication between the fifth front passage 514 and thethird front passage 484. Further, the heat dampers 528 in the form of abutterfly valve are rotated about the support axis, so that one endthereof blocks the eighth front passage 540 and the other end thereofblocks the seventh front passage 522, respectively.

On the other hand, the sub-defroster dampers 518 a, 518 b and thedefroster dampers 526 a, 526 b in the form of butterfly valves arerotated to establish communication between the fifth front passage 514,the sixth front passage 520, and the defroster blow-out port 524. As aresult, warm first air that has passed through the heater core 410 issupplied from the fifth front passage 514, through the sixth frontpassage 520, and to the opened defroster blow-out port 524, whereby warmair is blown in the vicinity of the front window in the vehicle. In thiscase, the second blower unit 412 is not driven, and only the first airsupplied from the first blower unit 406 is blown out.

In the foregoing manner, according to the second embodiment, because theforward bottom surfaces 416 a, 418 a of the first and second dividedcasings 416, 418 are configured to be inclined toward opposite sideportions of the casing 402, the size in the vertical direction of thecasing 402 can be reduced as much as possible, while moisture, whichpasses through the hole 456 a disposed at the lower portion of the firstguide panel 456 and is guided to the forward bottom surfaces 416 a, 418a, is guided to the first drain ports 454 a, 454 b that are disposed atpositions where the inclined surfaces of the forward bottom surface 416a, 418 a terminate, whereupon such moisture can be dischargedefficiently to the exterior of the casing 402. Furthermore, duringassembly thereof, even in the case that the casing 402 is positioned onthe floor or the like, since the pair of first drain ports 454 a, 454 bwhich project from the bottom of the casing 402 are disposed in a pair,the first drain ports 454 a, 454 b can be affixed stably as legportions.

The vehicular air conditioning apparatus according to the presentinvention is not limited to the above-described embodiments, and it is amatter of course that various modified or additional structures could beadopted without deviating from the essence and gist of the invention asset forth in the appended claims.

What is claimed is:
 1. A vehicular air conditioning apparatus includinga casing having a plurality of passages through which air flows, ablower connected to the casing for supplying the air to the inside ofthe casing, and cooling means disposed inside the casing for cooling theair and supplying cooled air, wherein on a bottom surface of the casing,a plurality of drain ports are provided, which communicate between aninterior portion and an exterior portion of the casing, the drain portscomprise a pair of drain ports disposed at opposite end portions in thebottom surface of the casing in a widthwise direction of the vehicle,and the bottom surface of the casing is formed such that a centerportion in the widthwise direction expands upwardly and the bottomsurface has inclined surfaces that decline downwardly respectivelytoward the opposite end portions in the widthwise direction of thevehicle.
 2. The vehicular air conditioning apparatus according to claim1, wherein the drain ports have cylindrical shapes, which extenddownwardly from opposite end portions of the casing in a widthwisedirection of the vehicle.
 3. The vehicular air conditioning apparatusaccording to claim 1, wherein the cooling means is inclined forwardlyand fixed in the interior of the casing, and a lower end portion of thecooling means is directed toward the drain ports.
 4. The vehicular airconditioning apparatus according to claim 2, wherein the cooling meansis inclined forwardly and fixed in the interior of the casing, and alower end portion of the cooling means is directed toward the drainports.
 5. The vehicular air conditioning apparatus according to claim 1,wherein a front side of the bottom surface of the casing is lowest andthe drain ports are disposed at the lowest front side portion of thebottom surface.
 6. The vehicular air conditioning apparatus according toclaim 3, wherein the casing further comprises a guide panel disposed inthe vicinity of the lower end portion of the cooling means so as to facetoward a lower surface of the cooling means, and the guide panelcomprises at least one hole disposed at a bottom part of the guidepanel.
 7. The vehicular air conditioning apparatus according to claim 3,wherein the casing further comprises a guide panel disposed on thebottom surface of the casing in the vicinity of the lower end portion ofthe cooling means so as to face toward a lower surface of the coolingmeans, and the guide panel comprises a hole disposed at a center and abottom part of the guide panel.